Hi @lbarbosa1
Welcome to the Auth0 Community!
As @Joe439Day mentioned, there might be some confusion, interference between the data of the action and the data of the form which could cause the issue at hand. If you could provide snippets of the form and action that you are using or if you can DM the tenant name so I can take a look myself, that would be great.
If removing the form action restores claims, consider handling claims separately from the form rendering process.
Indeed, setting a custom claim might be better if done in a separate action then inside the same on you are rendering the form in. However, if you need to access data from the form, that might not be suitable.
If you have any other questions, let me know!
Kind Regards,
Nik