Hi can anyone help me to solve this Dialogue thanks for all ​

(Hey ! Here is your help ! Hope it will help you :)

1) John: No thank you, this is all.

2) CD player, can I return it back ?

3) However, you must present us the problem with the CD.

4) If Something comes up, this is your only proof of purchase. Without this proof, we can not give you a refund even if there is a problem with the CD.