How To Update field in database table using Foreign Key?

Hello evryone, Actually I' m working on reactjs project with laravel API. I have table named status and another named complain. the STATUS table has a forign key from complain Table . I want to create a put API but with condition like this eg: if primary_key==foreign key then update values in mother table. This is my Attempt without any condition:

        public function updateStatus(Request $request, $compl_id){
            $data = $request->validate([
                'compl_job_status' => ''
            ]);
            $input = $request->all();
            $compl = complain::findOrFail($compl_id);
            $compl->update($input);
            if($compl->save()){       
              return response()->json([
                'message' => ' Updated Successfully !',
                'status' => 200,
            ]);}
            return $compl;

        }

PS: the foreign key in the other table is named complain id this is the mother table :

     Schema::create('complains', function (Blueprint $table) {
            $table->increments('compl_id');
            $table->unsignedInteger('building_id')->nullable();
            $table->foreign('building_id')->references('building_id')->on('buildings')->onDelete('set null');
            $table->unsignedInteger('user_id')->nullable();
            $table->foreign('user_id')->references('user_id')->on('users')->onDelete('set null');
            $table->string('compl_title',200);
            $table->string('compl_description',1000);
            $table->date('compl_date');
            $table->tinyInteger('compl_job_status');
            $table->string('compl_assigned_to',100);
            $table->string('compl_solution',500);
            $table->string('compl_complainBy',100);
            $table->string('compl_name',250);
            $table->json('compl_pictures');
            $table->string('compl_email',100);
            $table->string('compl_phone',50);
            $table->timestamps();
        });
    }

this is the othe table:

 Schema::create('statuses', function (Blueprint $table) {
            $table->increments('status_id');
            $table->unsignedInteger('complain_id')->nullable();
            $table->foreign('complain_id')->references('compl_id')->on('complains')->onDelete('set null');
            $table->unsignedInteger('user_id')->nullable();
            $table->foreign('user_id')->references('user_id')->on('users')->onDelete('set null');
            $table->tinyInteger('compl_status');

            $table->timestamps();
        });

Any suggestion Please !