Angebot

Recently you had Angebot, I made contract with O2 for 2 years last month on April 16 and after a week I took Samsung S20 Fe in one of your  branches which is in Roederplatz, and before taking the phone I asked them:  "is it possible to do it without 39.99 ,as shown in Angebot ,  they told me "Yes, if you take the phone " but now I take the letter that I must pay this 39.99 euro.  My clientnumber is xxxxxxxxxxx, please, help me to solve this problem, my phone number is +49xxxxxxxxxxx

(Customer data removed, o2 Michi)

But  shop told me that they should ask the main office can the main office present the sale

And did the shop ask? What was the 39,99 for? 

Who is 'you'? What offer? This is a forum where customers help each other.

Again: If an o2 shop offered you something then the shop is responsible for that and needs to resolve any problems.

No, you posted (twice!) your text in the discussion forum in which primarily customers help each other. Nobody here knows what offer you are talking about or what the 39,99 are unless you provide more details. So far you have only said that a shop promised you a discount which was not in the contract and in that case you need to clarify it with the shop.