Discord refuses to remove my phone number attached to my account

Hi, there's this situation i currently have with discord support, that they refuse to delete my phone number from my account. Basically every time i try to manually remove it, my account gets locked up until i add another phone number in order to continue accessing the service, "for security reasons" with no option for email verification (of course).

I contacted the support team asking for clarifications and if they could remove the phone number and, in short, they said that they couldn't do that since my account was flagged somehow, and that they won't remove the phone verification...

Now, what are your opinions about this? Should i use a free voip number site in order to replace my real phone number with the fake one? My concern is that i don't know who could own that number so i don't know if it's safe to trust it, and i'm not willing to spend any money for this