This is one of the worst experiences I ever had since I came to study and live in Frankfurt. I have…read morehad a lot of unsuccessful returns of those bikes (not from my mistakes) where I always had to call their Call Center Agents and explain the situation, but last night I had enough!!! After a "Successful Return" on the display of the bike I went home and after 20 minutes I saw that the bike wasn't returned and I had to go back and fix the problem. BTW it was 3 o'clock in the morning! When I returned I tried to enter again the CODE, but it said that it was incorrect! So the bike was somehow returned, but didn't register in the app. And now you will say that it takes time to show in the app, but why it registered with the extra time so now I have to pay thah extra time that took me to realize thah the bike wasn't returned. I will never use them again!