I have had the same problem! (See my topic: Not able to bid after first round)
I have no idea why dude, I had this problem a while ago aswell after round 3 or something. But this time it was on ma laptop! So weird.. thankfully I won the auction cus nobody bid after me, but so weird!
Mine was a Nordeus player as u can see in the screenshot of my topic. Maybe thats why? ANd mine was a 3 player (lowest u can get in the transfer market) and all other players at the auction were 2 lvls lower than myself.