Unable to make changes on flex form

Summary:

User gets an excel message every time he tries to change rows in flex form.

Content (required):

Hi, one user is getting a message from excel when he tries to change rows in flex form, saying the sheet is unprotected and may corrupt the form, this is not supposed to happen with a flex form as far as I know. Other user with the same form does not have any problem. Could be an excel or smart view version issue? This user has the last version similar than others. Also, the form is setup with [disabled sheet protection]. Attached is the excel message.