Thank you for posting this in Microsoft Q&A.
As I understand you are able to see multiple directories under manage tenants and also under directories and subscription.
It looks like your account is still present in your old companies directories.
The only way to fix this is by contacting them and ask them to remove your account from there directory. Your account will be provisioned as a guest account in your old company.
Let me know if you have any further questions.Please "Accept the answer" if the information helped you. This will help us and others in the community as well.