[skunt3m]

Teams are allowed 50 players under contract as per the NHL CBA.

"Total NHL contracts per team = 50 (including two-way contracts and NHL contracts in the minors), players who are meet the following three conditions do not count to this limit: 1. The player is 18 or 19 years of age. 2. Is in a junior league, and 3. who have not played 10 NHL games the current season"

You might be running into the limit. You can check and see where you're at under Team > Roster > Contracts. Your number/50 is displayed at the bottom left of that screen.