I understand you said you cannot access your account. But was it just the 2FA problem? If so, you can 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 really cannot login even with Send email option, please message support agent
https://productioncommunity.publicmobile.ca/t5/notes/composepage/note-to-user-id/22437
If you can login with the help of email to receive 2FA code, go to My Account to request Change Sim card (please note that due to some glitches, accessing change sim care from mobile phone or tablet might not work for some accounts, you might want to use make a change sim card request on a desktop or laptop computer )
(If you are unable to login as you don't have a phone 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)
After you logged in, unsuspend first if you have suspended your service earlier
Then go to Profile page, click on the Pencil besides the sim card number, follow the steps to enter the new sim card number and complete the change sim card request
(or direct link: https://myaccount.publicmobile.ca/en/account/profile/change-sim-number )
After the sim card is updated, wait 5 mins, then reboot your phone and it should be good
