None of my players want to renew a contract

I started with Oldham in league two brought in some free agents and youth players but I am now in my 4th season, up to the championship and have not been able to renew a single contract, I get the free agent I bring in that are probably too good to be playing league 2 and league 1 not wanting to resign but even players that I have brought up through the youth system and players that were originally at the club won’t resign.