Cancelling order

Dear Team,

This is approximately the 4th forum where I tried to get in touch with O2. I ordered a service via Check24 on the 9th of Jun. I went through on every step. I was called about the assignment also received the sms about it, but since then O2 just stopped to reach me out. Once I sent an email about my status they just sent me back that I need to provide the contract details of the previous tenant (it was not mentioned previously and I do not have this information). I believe for both parties the best solution is to cancel this order.
This is absolutely unacceptable that I have been waiting for the internet for almost a month and O2 is not responsive at all..

Thank you,
Gabor