I don’t have access to my Apple ID's trusted number

You’re logged in here w/ a trusted device (or 2FA) so you can easily update your trusted numbers.

See how here:

Two-factor authentication for Apple ID - Apple Support

Follow the directions under the topic heading, “ Turn on two-factor authentication for your Apple ID”

Ok … but do you still have a trusted device for the AppleID under discussion (i.e. the one for which you want to update the Trusted Numbers ???)