Please excuse my ignorance: Did you cube the chicken and/or cook/process it in some way before you canned it? (Still have to learn canning.)
still learning to can
BTW- you are not ignorant, you are learning, and that is good.
Get a Ball or Kerr canning book, or get canning information from your county extension office, or Putting Food By etc and go for it. Yes it costs a bit to get going, but you use the jars over and over (rings yes, flats no, they are a one use item) and there is so much one can do if you combine canning, drying, freezing if you wish, with whatever garden you can have, or reasonably buy at a farmer’s market that is fresh.