Contact with pause and extension following the number dialing incorrectly
I have an iPhone 12 iOS 16.4.1. I created a contact that has the usual area code, 7 digit number, then a pause (inserts a comma) followed by a 4 digit extension. I manage the phone system of the number being dialed from the contact. The call is answered by an auto attendant. After the initial greeting you can enter an valid extension number to have the call transferred to it.
What ends up happening is the second digit is repeated, and so the last digit is never dialed. This often results in the call either going to the wrong extension, or getting an invalid extension response from the attendant. For example: an extension of 3456 results in the attendant interpreting it as 3445.
I created the exact same contact on a different iPhone (iPhone 8 on iOS 14.2) and there is no issue. Both phones are on the same carrier, and same corporate shared plan.
Seems like a possible iOS issue. Are there any known dialing issues from contacts on iPhones with iOS 16 and higher. One of our employees reported this issue as starting early to mid March of 2023. Close to iOS 16.4 release?