iPhones not showing proper caller ID with Follow-Me on

Hello,

I am running FreePBX 13.0.54 and Asterisk 13.7.0.

I am trying to get the follow-me settings dialed in for my co-workers but am having problems. I use a Samsung Galaxy but our organization uses iPhones for its mobile work phones. On my Galaxy, extension numbers show when using Follow-Me but on the iPhone calls from extensions show as UNKNOWN.

The problem seems to exist at the “Change External CID Configuration” under the Find-Me/Follow-Me settings of the extension. If I set the CID to a 10 digit fixed value, then the iPhone will display the number. If I allow the CID to be transmitted then the iPhone shows UNKNOWN, but my Galaxy will show the 4 digit extension number without a problem.

So just to be clear, if extension 2000 calls extension 2001 and after ringing for a bit goes to the Follow-Me setting, then my Galaxy will show 2000 but the iPhone will show UNKNOWN.

Has anyone experienced this as well? Are there any solutions aside from going iPhone to iPhone creating contacts for the extension numbers?