SQL query to update a column to be foreignId and onDelete Cascade

I'm working on a live laravel website on cPanel and I'd like to update the user_id column on the properties table to be foreignId and onDelete Cascade.

I have tried the following:

ALTER TABLE properties
ADD CONSTRAINT fk_properties_user
FOREIGN KEY (user_id)
REFERENCES users(id)
ON DELETE CASCADE;

But it's not working(deleting a user doesn't delete its associated property) and I'm getting the following response when I execute the command above:

MySQL returned an empty result set (i.e. zero rows). (Query took 0.1913 seconds.)

ALTER TABLE properties ADD CONSTRAINT fk_properties_user FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE