Can't access my apple ID as it was linked to a phone number I no longer have access

Hi, my apple ID was previously linked with a phone number I no longer have access to (it was a company phone and I've switched company recently).

I got myself an Ipad and wanted to use my apple ID to it, but with the 2-step authentication, its asking me for the code its sending to the phone number I no longer have access.

Anyone can help?

I've went through the apple ID website, even gave them my credit card info to prove my identity and help me change the phone number my apple ID is linked to, but its still telling me to wait. This is frustrating...