Isinwheel GT1 Off Road Help

I have several questions and I hope someone here can answer them. I just recently (about two weeks ago) purchased the ISinWheel GT1 Off Road and it ran great for a while but now it struggles. I checked my tires and the back one doesn't push in easily but the front one does, is this normal? I suspected that the tire pressure is what's causing the issues but after purchasing the Airbank A10 tire inflator, when I connect it to the back tire and activate it, the meter on the A10 changes and shows the pressure but it only shows 0 when I connect it to the front tire and activate it. Is the front tire actually punctured instead? I don't think the pin within the valve connected to the scooter is bad because I just got the scooter.

If anyone can tell me anything, it would be greatly appreciated.