Hello @cbmnine,

welcome to the o2 community and thank you for your contribution!
Technical problems can always occur. Sometimes the website is being worked on, which is why logging in doesn't work for a short time. If you are trying to log in on a laptop or in a web browser, try a different browser first.
Alternatively, you can also log in to the app as described there.

General: Have you already registered your phone number? If you have not yet registered, logging in will not work either.

Kind regards
Jessi

My sim card is locked. How do I get PUK number? I tried to calling customer care but they don’t understand English. 

Hello @cbmnine,

I thought you couldn't register in My o2?
But you really mean that you can no longer use your entire sim card?
Generally, you will find the PUK in your mobile phone documents, which you received when you signed the contract. Alternatively, you can register in My o2 (please answer my questions about this, can you register there or not?). The respective hotline numbers, including the English hotline, can be found here: Click.

Kind regards
Jessi

Thank you. I visited the store and they helped me.

Hello @cbmnine, 

thank you very much for the feedback! 
I am very happy to read that everything is working now. 

If you have any further questions or concerns, please feel free to contact us in the community. 

Kind regards
Jessi