Create information form within account tab

I have used Ultimate member in a car club site. I would like to know if I can attach an informational form for members to add details of their vehicles which will show up when they click on the Account tab.
I have created a form with form type of register which shows up in the list of Account, Change Password, Privacy and Delete Account.

When I click on it the form displays and I have a few fields Make, Model, Year.

I can enter details into the fields and click Submit but get an error
An error has been encountered.
Probably page was cached. Please try again.
i have disabled cache in the plugin changed define in the the WP-config.php file to false but still get the error. Have cleared cache in the browser and note that others have had this problem in the past.

I am running this playpen site under Flywheel Local so whether this is contributing to the issue I don’t know.
Any suggestions welcome