Given that it's happening on your computer and your phone and nobody else has had the same issue (I also use Chrome with no problems) I can only assume like PS that it's something on your side.
Maybe you've got a specific set of training routines that the website just doesn't like? I'm clutching at straws, sorry
As for what else you could do...maybe try changing one player's training at a time and see if anything works? Or set them all to one routine (training match/rest/cross country/etc)?
If that all fails then my only guess is that a Mod/Ron may be able to reset your training in some way...but I've no idea how, or if it's possible.
As I asked before - are your players actually training with the routines you've got them on at the moment?