First, please make sure that the name (or ID) of the bike you are standing in front of matches the name (or ID) of the bike you rented within the Avocargo App.
If this is the case, a spoke may be blocking the U-lock. To solve the problem, move the rear wheel a few centimeters forward and backward. Then press firmly on the lever on the U-lock (on the opposite side of where the chain lock is inserted) until it beeps and then go into parking mode via the app. You can then try to unlock the bike again.
Spoke blocked U-lock -> move rear wheel -> press lever down on U-lock (until beep)-> park mode -> unlock again.
If you still encounter issues, please contact our Customer Care Team.