Player demands new contract but then won't let you offer one

[AndyDan32]

Hello! I am playing as Tottenham and signed Andrea Belotti. At the end of my first season he demanded a new contract and I agreed to start negotiations. When I went to offer him a new contract his agent said he was not interested in opening negotiations. Is this a glitch?

 

[JosefJoseph]

I've had players demand new contracts less than 6 months after their last one (no changes in squad status), almost as bad as backup players who are playing most weeks, due to good form or injuries, complaining about a lack of first team opportunities.