How do I remove my personal gmail that is linked to an old place I worked for.

Hello, I have an issue with an old tenant that my microsoft account is linked with. I used my personal gmail email and can't remove it now from that tenant. I already wrote to the previous employee to remove me from their organization but apparently they have technical issues to do so even after I explain step by step and provide links and screenshots to the person who has admin role there. Is there another option where I can reclaim my own account as for couple of years I have nothing connected to them but need my access to microsoft services and have issue with that. I really prefer to keep my current account and wish not to create a completely new one. Thanks!