Barclays Credit Card Complaint

Barclays Credit card department,

New Jersey

- - offered me a $20.00 discount on my $330.00 in store purchase if I applied for their credit card. I applied and the discount was not taken on my purchase. I asked that the application be stopped but the salesperson said it was too late. She said I would receive a check for $20.00 in the mail in the next weeks. A month later and still no check. I called barclays who said I would n't be receiving any points until I made more significant purchases! I asked them to take the card off my credit report and they refused. Please help.