Yes I have been using the same authorized MFi supported accessories for about 6 or 7 months. I initial thought that it might be the USB cable so I purchased a new cable and the problem was exactly the same. I believe the problem started shortly after the IOS 15.1 update. I am still able to charge other devices (iphones and ipads) which have the older Lightning cables using the same Ravpower supply - zero problems. I have used the USB C cable and power supply on other devices without problems. Judging from this behavior, it appears that some way, some how, the new IOS is determining that the USB C devices are not compatible. This appears to me from the odd behavior that the bug is in the 15.1 update. Let me give you some recent examples. Last night I plugged in the usb c cable and power supply and the little lightning bolt in the battery popped up and the iPad was charging. This morning the lightning bolt was gone and when I when into the battery settings I could see that the charging stopped after 3 hours and never turned back on. While trouble-shooting with Apple support, they had me restart the iPad and sure enough the lightning bolt showed up after the restart, but then, about 5 minutes later, without touching the iPad, cable or anything, it suddenly disappeared.
Of course when I talked to Apple support and they gave the party line that if it is not an Apple Branded accessory - I should go talk to the device manufacturer (Ravpower) (the assumption being that the IOS update has nothing to do with the problem). So I called Ravpower customer support and they are looking into problem and will get back to me.
I am just asking if others have had similar problems or is my power supply going bad or is out-of-date given the new IOS updates. I also wish that the technical support personal would stop drawing lines when it comes to non-Apple accessories. These companies are paying Apple a Licensing fee to use the MFi technology for the very reason that Apple requires that these devices are within the specifications to interface with apple products. I know this is a big issue in Europe right now with the EU essentially demanding that all iPhones sold there have standard USB c interfaces - but it would be better if the technicians could troubleshoot with MFi approved accessories attached.