Dell Ac Adapter Doesn’t Charge

Hi, I have a Dell laptop and the power adapter is plugged in but no longer charging the computer. I can get it to work once in a while if i mess around with the plug but once i move the laptop it instantly stops charging again. Does anyone know what’s wrong? Is it the laptop or the adapter? I just got a new Adaptor this pass October think it was my old one that was messed up. BUt it wasn’t. Now This new one that i just got doesn’t work anymore. Did it short out? So now i can’t charge my laptop. I don’t know what to do. Pay another $75 for another charger that probably won’t work. Dell computers suck.