Hi @HomeOffice4us - hope you're keeping well!
You're unable to open a ticket because you should be posting here instead for assistance! We're able to help here, and it's a peer-learning environment where others can also learn and contribute to finding solutions!
It sounds like you're a bit confused, but I'm sure we can help.
AdSense being managed by Ezoic is completely unrelated to the Ad Manager/Multiple Customer Management process with Google, so we'll need to separate the two.
Again, it sounds like you're aware that Google disapproved your application for Multiple Customer Management for having multiple accounts. That means we'll need to gather a bit more information about what emails you are using to apply.
https://support.ezoic.com/kb/article/applying-to-google-ad-manager-multiple-customer-management
Which email do you use for Ad Manager currently?