I have found a partial way around this if you don’t need the flash. I didn’t realize there are two buttons. There is the main one with the red on the front but the other one is just behind it and hangs down. This is for shooting thru windows. I have gotten it to charge long enough to get film out of the camera. I noted that this pack expired 2018, I bought it 2019. So odds are the new batteries don’t last as long as the old ones even though usually when I get thru a back , I can take that battery out and still have 5-6 volts left on the battery (good enough to ruin an LED to test. (1.5/3 volts max 6 volts no! I have managed to charge some phones cutting the bad USB micro cords and reusing those. pretty much any crappy new micro only usb cord would work. mini usb and usb c I haven’t had issues with those. Thats just for recycling the battery power. WD-40 makes a contact cleaner but where the heck do I shoot it in for flash contacts , I know where the power ones are although usually you need something to rub it out and rubbing the sparky battery isn’t a good idea.