I confirm this issue, it is because Toolset Forms, when you create a form the first time will store that form in the native Posts Table, and give it a post_name, post_title as you set the Forms title.
Later, when you update that Form and change it's Title, only post_title, but not post_name gets updated in the database.
This is like when you edit a Post or Page in WordPress and change the title.
The slug won't change, you'd have to edit that manually, and separately.
This is the same here, just, Toolset Forms misses the slug edit part - so you can not manually in the admin change that slug at all.
This is mainly because several people did what you did but then wondered why the forms stopped working.
(They forgot to update the slugs in the ShortCodes.)
So, I see both reasons, you want to change the form's name and can't, others want to avoid that changing the name only breaks their setups (maybe they have many places with that slug used, hence they prefer to leave it)
I see as a possible solution to this a feature to be added:
A slug edit field in the Forms, where you can decide if you want to update just the title (as in WordPress native pages and posts) or as well the Slugs (as it is possible in Content Templates and Views, for example).
For your current solution you have 2 choices:
- delete the form and recreate a new with right name
- edit the database, change that posts post_name, and update your shortcodes.
However, I assume you would prefer an Admin step by step description, hence the solution is to copy that current form's content, and create a new one, delete the old one.
I will ask for that slug edit field to be added with a certain priority.
If we add safety we cannot remove edit rights 🙂
