[Android Central Question]

He can I stop receiving in call UI blocking incoming calls

[Rukbat]

Blocking has to wait until after the first ring to get the callerID (that's when it's sent) to know to block the call. You can't block that first ring. (If your carrier blocks calls, that might stop the call from getting to the phone at all, but if you're blocking a lot of calls, they may not block them all - they may have a limit. And if you're trying to block robocalls, it won't work - the "callerID" is a random number for each call. If the same robodialer calls you 5 times in a row, it would have 5 different "callerIDs".)

[ManiacJoe]

If the problem is that calls are being blocked when you don't want them to be, see the settings in your dialer app for "block" or "reject" calls (or similar wording).

[B. Diddy]

Welcome to Android Central! You need to clarify what you mean. InCallUI is the system app that controls the user interface while you're in a call. It wouldn't be blocking anything.