In-App Purchase Error: "Invalid application external version."

I found this in my App which is in Production. Specifically,

Code Block 
Error Domain=ASDServerErrorDomain Code=3512 "Invalid application external version."

The device is iPhone 11, iOS 14.3.

In App Store, the app version is "x.y.z"(6.0.0, for instance), while in the app info.plist, versions are:

Code Block 
CFBundleIdentifier: 6.0.0,
CFBundleShortVersionString: 100

(legacy problem)
I wonder if it is because the CFBundleShortVersionString version not matching the appstore version.

Another issue:

Code Block language
Error Domain=SKErrorDomain Code=2 "Cannot connect to iTunes Store" UserInfo={NSLocalizedDescription=Cannot connect to iTunes Store}

This is commonly seen in lower iOS versions(<iOS 14.0).(SKErrorPaymentCancelled, but actually usually not cancelled by the user)

If anyone has any idea(or apple documentation or the specific error reason), please let me know. thx.

And, some other issues, please help @Apple

---

Code Block language
Error Domain=ASDErrorDomain Code=907 "Unhandled exception" UserInfo={NSUnderlyingError=0x2813b0630 {Error Domain=AMSErrorDomain Code=6 "Payment Sheet Failed" UserInfo={NSLocalizedDescription=Payment Sheet Failed, NSLocalizedFailureReason=Payment sheet cancelled}}, NSLocalizedFailureReason=An unknown error occurred, NSLocalizedDescription=Unhandled exception}

commonly seen on iOS 14.0+

Code Block language
Error Domain=ASDServerErrorDomain Code=2037 "Your Purchase Could Not Be Completed" UserInfo={NSLocalizedDescription=Your Purchase Could Not Be Completed}

seen on iOS 14+

Code Block language
Error Domain=ASDErrorDomain Code=825 "The operation couldn’t be completed. (ASDErrorDomain error 825.)" UserInfo={NSLocalizedDescription=The operation couldn’t be completed. (ASDErrorDomain error 825.)}

seen on iOS 14+