This is what i got in response

Offers approval depends on the advertiser, not UpPaid.com, we only establish a link between you and our advertiser.

Your offer can be declined because:
- your IP as already registered a signup: you could have completed the same offer on other site or you have a dynamic IP and other person has already completed the offer from that specific IP.
- you did not complete the offer correctly
- you completed offers that don't apply for your country
- other reasons that only the advertiser knows

We are really sorry if the offer you submitted was rejected because this isn't good for us either, we lose clients and you lose time. We hope to add more offers soon for you to complete.

Thank you for your understanding
All these are really excuses. non of these points relate to me yet my offer got rejected. Not only one every offer i submit gets rejected.