Having issues with the PUT requests with my Many to Many relationships.

The user cannot edit the tags field since the drop down won't show all the possible tags.
When submitting the PUT request I'm getting an duplicate entry error.

Background: I'm building a decision tree. The 'tree' are the decision tree pages and I'm attaching 'tags' to them to help categorize them. The many to many are tag_tree. I'm able to create a new tree page, and the user can see the drop down and select the appropriate option and I'm able to save to db fine.

Any hints on how to post code into the threads would be helpful as it seems only certain code shows in the cool boxes where other doesn't not....:)

TreeController.php:

public function index()
{

    if (request('tag')) {
        $trees = Tag::where('name', request('tag'))->firstOrFail()->trees;

    }

    else {
        $trees = tree::latest()->get();
    }


    return view('tree.index', ['trees' => $trees]);
}

/**
 * Show the form for creating a new resource.
 *
 * @return \Illuminate\Http\Response
 */
public function create()
{
    return view('tree.create', [
        'tags' => Tag::all()
    
    ]);
}

/**
 * Store a newly created resource in storage.
 *
 * @param  \Illuminate\Http\Request  $request
 * @return \Illuminate\Http\Response
 */
public function store(tree $tree)
{
    request()->validate([
        'name' => 'required',
        'description' => 'required',
        'links_to' => 'required',
        'tags' => 'exists:tags,id'

    ]);

  
    $tree->name = request('name');
    $tree->description = request('description');
    $tree->links_to = request('links_to');

    $tree->save();
    $tree->tags()->attach(request('tags'));

    return redirect(route('tree.index'));
}

/**
 * Display the specified resource.
 *
 * @param  \App\tree  $tree
 * @return \Illuminate\Http\Response
 */
public function show(tree $tree)
{
    return view('tree.show', ['tree' => $tree]);
}

/**
 * Show the form for editing the specified resource.
 *
 * @param  \App\tree  $tree
 * @return \Illuminate\Http\Response
 */
public function edit(tree $tree)
{
    $tags = \App\Tag::all();
    return view('tree.edit', compact('tree', 'tags')) ;
}

/**
 * Update the specified resource in storage.
 *
 * @param  \Illuminate\Http\Request  $request
 * @param  \App\tree  $tree
 * @return \Illuminate\Http\Response
 */
public function update(tree $tree)
{
    request()->validate([
        'name' => 'required',
        'description' => 'required',
        'links_to' => 'required',
        'tags' => 'exists:tags,id'
        
    ]);

    $tree->name = request('name');
    $tree->description = request('description');
    $tree->links_to = request('links_to');
    
    $tree->save();

    $tree->tags()->attach(request('tags'));

    return redirect(route('tree.index'));
}

/**
 * Remove the specified resource from storage.
 *
 * @param  \App\tree  $tree
 * @return \Illuminate\Http\Response
 */
public function destroy(tree $tree)
{
    //
}

}

Tree edit.blade code:

                 <form method="POST" action="/tree/{{ $tree->id }}">
                    @csrf 
                    @method('PUT')              

                    <div class="py-2 px-2">
                        <label class="block" for="name">Name</label>
                        <span class="text-gray-700"></span>
                        <input type="text" name="name" id="name" class="form-input mt-1 block w-full" value="{{ $tree->name }}">

                        @error('name')
                            <div class="text-red-500 text-xs italic">{{ $message }}</div>
                        @enderror

                    </div>
                        
                    <div class="py-2 px-2">

                        <label class="block" for="description">Description</label>
                        <span class="text-gray-700"></span>
                        <textarea type="text" name="description" id="description" class="form-textarea mt-1 block w-full" rows="3">{{ $tree->description }}</textarea>

                        @error('description')
                            <div class="text-red-500 text-xs italic">{{ $message }}</div>
                        @enderror

                    </div>  

                    <div class="py-2 px-2">
                        <label class="block">Select Category</label>
                        <label class="text-xs">(Hold Control to Multi-Select)</label>

                        <div class="md:flex mb-3">

                            <select type="text" id="tags" name="tags[]" class="form-select block w-full mt-1">

                                @foreach ($tree->tags as $tag)
                                    <option value="{{ $tag->id }}">{{ $tag->name }}</option>
                                @endforeach
                            
                            </select>
                        
                        </div>

                        @error('tags')
                            <div class="text-red-500 text-xs italic px-2">{{ $message }}</div>
                        @enderror 
                    </div> 


                    <div class="py-2 px-2">
                        <label class="block" for="links_to">Link</label>
                        <span class="text-gray-700"></span>
                        <input type="text" name="links_to" id="links_to" class="form-input mt-1 block w-full" value="{{ $tree->links_to }}">

                        @error('links_to')
                            <div class="text-red-500 text-xs italic">{{ $message }}</div>
                        @enderror

                    </div>              



                    <div class="py-2 px-2">
                        <button class="bg-blue-500 hover:bg-blue-700 text-white font-bold py-2 px-4 rounded">
                            Submit THE Changes
                        </button>
                    </div>


                </form>
                
                <form method="POST" action="/tree/{{ $tree->id }}"> 
                    @csrf 
                    @method('DESTROY') 
                     
                    <div class="py-2 px-2">
                        <button class="bg-red-500 hover:bg-red-700 text-white font-bold py-2 px-4 rounded">
                            Delete Page
                        </button>
                    </div>
                </form>



        </div>

    </div>
</div>

Error:

SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1-3' for key 'tag_tree_tag_id_tree_id_unique' (SQL: insert into tag_tree (tag_id, tree_id) values (1, 3))

Attach and Validate Many-to-Many Inserts

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