You already setup a PM account? can you login your My Account? Maybe use email to receive the 2FA code?
(On the screen it is expecting you to enter the code, click Didn't get the code? or Resend code and then choose Send email)
If you can login, go to Profile page, click the pencil besides the phone number and you can choose a new phone number
If you cannot login My Account, open ticket with PM support and they can help:
**Monitor your Community inbox (envelope icon on top right) after the ticket is opened. CS Agent will reply to you there
