[Gretl-users] object could not rebuilt

I work with gretl v 2023a (32bit) on Win7. So far I had no problem saving and retrieving sessions. Recently, after deleting renaming  and saving nls models in sessions. I can not retrieve them.  Most of the time I can retrieve up to 3 nls models, while I can retrieve aw many as a have OLS models.I reinstalled the gretl deleting everything but still have the same problem.Thanks in advance