Due to work reasons, I had my account associated to multiple Azure tenants, but when I have finished one project I try to de-associate my account from those tenants that I joined in the past and I no longer use.
Could be normal to ask to the suscription admin to do that for you, but I want to share how to do it by yourself in a few simple steps.
First of all, let’s check your actual subscriptions associated to your account, so log in into Azure Portal, and next click on subscription:
Once this has been done, log into the next url: https://myapps.microsoft.com and then click in your account in the upper right corner. From there, you can see all the organizations where you account is associated with:
Click on the gear icon, and you will be redirected to your profile page, where is it possible to leave the organization by clicking on Leave organization link
Once you have leaved the company, reload your Azure Portal, and you will no longer see the organization/subscription you have left.
Albandrod's Memory 