I have created a custom role for potential customers with which they can fill in and save the details of their store. It is possible to add data, but the form to edit the data is not visible. However, I have the option checked to edit their own posts.
Is there any documentation that you are following?
Yes, the general tutorial for membership sites
Is there a similar example that we can see?
no
What is the link to your site?
the specific url to edit your post is this (you need to have an account to access it): hidden link
However when I try to log in they don't seem to work. Can you check on them on your end and let me know if you're able to log in with these credentials ?