Coz when u r going around your cellular is jumping from one cell “tower” to another and is on that transition that iOS is not being able to “close” session on cell A before leaving then is not opening session on cell B because it’s is “already opened” my iPhone 11 with movistar (Spain) the modem firmware from 14.3 to 14.4 beta 1 was “upgraded” from 2.03.04 to 2.03.03 and I had almost no issues... on 14.4 beta 2 again the firmware is 2.03.04 and problems appeard so... sincerely I don’t understand how it is being so difficult for developers to find the root cause.... being IT “guy” sin more than 24 years I can’t understand at all this ... first and most important that has to work on mobile is: data and call when MOVING around ;))) so really upset with this....