iPad not charging or charging very slowly

my iPad is having trouble with charging. When it’s plugged in, the battery percentage goes down. I left it on charge for five hours and it only charged up to 20% I know it isn’t the charger that is the problem becuase I have tried at least four different chargers. I brought the iPad just after a year ago and so my warranty has run out. I cannot afford to buy a new iPad. Is there anything I can do to fix my issue?