Unable to change trusted phone number

Hi Stewbert218,

For help with the Apple ID, you may need to start the process for account recovery. The information below found in the article here can get you started: How to use account recovery when you can’t reset your Apple ID password - Apple Support

"What is account recovery?

Account recovery is a process designed to get you back into your Apple ID account when you don’t have enough information to reset your password. For security reasons, it might take several days or longer before you can use your account again. We know this delay is inconvenient, but it's important so that we can keep your account and information safe.

Before you start the account recovery waiting period, try to reset your password. 

• Learn how to reset your Apple ID password on a trusted device or through the Apple Support app on a family member’s iPhone, iPad, or iPod touch. You can also visit an Apple Store and ask to use a device on site.
• If you set up an account recovery contact, they can also help you reset your password. 

Use account recovery only as a last resort when you can’t sign in or reset your Apple ID password."

Reach out to Apple Support directly if you have any issues with the steps or further questions about the steps.

Contact - Official Apple Support

Contact Apple for support and service - Apple Support

Best.