I got a response from *** Email address is removed for privacy ***.
It took me two episodes, but the second guy was very workable, sent me replacement T6s, saying they had addressed the issue. They worked immediately on my Windows 11 system.
I had previously sent my email to Tozo at "info_at_tozostore_dot_com". Is there a different address for support I should use? I could not find any other link their site.