Problem with combobox form controls

I contacted the support chat included with my Microsoft 365 subscription and was told that they didn't know about Access, except for installation and activation issues, and that I had to request assistance by accessing a link that brought me here, so despite knowing the nature of this invaluable forum, I posted thinking that official Access technicians were also here. I am sorry for the misunderstanding.

That said, I greatly appreciate your interest and would be happy to upload my acddb, but at the moment it is unfeasible, as it is a complex and very bulky development that requires going through an online installation and activation process without which it is impossible to start it, so it would be useless.

I would like to point out, in any case, that if the forms works perfectly in Windows 10 and the problem occurs only in windows 11 (I have already tested in two different machines) being something apparently as basic as the population of the text of a combobox while writing in it, it must be because something has changed in the operating system, without Access has adapted to it (I know it sounds strange, but I really can't find another explanation) and that's why I tried to request support, because I am developing with access and VBA for nearly 30 years and normally able to find what is my fault.

In the next days I will continue trying to isolate the problem to prepare and upload a trimmed version that allows to check what I say.

Thanks again.