Transformations in geographic reference systems absent

[AngeloTroiano]

Hi,
I have an arcmap 10.8 and the moment I try to perform a transformation from one reference system to another I do not have the option to choose any transformation (either via project tool or directly in map when I assign a reference system to the map). The transformations drop-down menu is empty. I have tried doing a software repair and also uninstalling and reinstalling but the problem remains.

Thanks