Can't make loan offers

I just started a new save on FM20 with York City, in the National League North, and cannot make a loan offer for any player, even those listed for loan.

The transfer window runs season long in the non-leagues so I know it isn't a time-frame issue. I have 0 players on loan currently so I also know it's nothing to do with restrictions.

Has anyone else come across this, or does anyone have a clue what could be preventing me from making an offer?

@BEN_NFFC87 What does it say when you hover over the loan offer option with your mouse?

Unfortunately, nothing. Looking into it further, I can loan players from other non-league teams, but can't make an offer for a league player.

I thought it might allow me to do so after the league transfer window shuts, but nothing.