sample letter for inform about new Sim card no?

[Your Name]
[Your Address]
[City, State, Zip Code]
[email Address]
[Date]

[Recipient's Name]
[Company/Organization Name]
[Address]
[City, State, Zip Code]

Dear [Recipient's Name],

I am writing to inform you that I have recently changed my mobile service provider and now have a new SIM card number. My new number is [your new SIM card number]. Please update your records accordingly.

Thank you for your attention to this matter.

Sincerely,
[Your Name]