Hi Gayle,
Welcome to the forum. There are many people working on note bending in free reed instruments. It is a very complex subject and not an easy thing to do on a melodica or harmonica for that matter.
I am finding the harmonica websites provide a wealth of information that can be applied to the melodica.
Here is an article on free reed instruments and note bending:
This forum as a search function that can root out posts on bending and tuning. I will try to answer you questions on bending in another reply to one of your posts.
Regards,
Lowboy