You may want to try to get a credit card from another company. The following article from Bankrate.com https://www.bankrate.com/credit-cards/bad-credit/how-to-build-credit-fast/?tpt=b#ways-to-build-credit
has some tips for building credit including the following excerpt:
If you have no credit history or poor credit, you can explore credit cards that are easier to get approved for. Retail credit cards tend to require only a fair score, so check to see if your favorite store offers its own card. Student credit cards can also be a good option if you’re new to credit.
If you’re having trouble getting approved for a card, you may need to explore secured credit cards. You put down a deposit (like $500 or $1,000), and that amount becomes your credit limit. The lender will report on-time payments on the account to the credit bureaus.