Could be a couple of reasons. One as someone else has mentioned, you are self employed......Big banks hate this. Secondly, for credit cards, they look at your credit limit, not how much you own on it or your prompt payments. Thirdly, your loan amount might be below their internal threshold. Banks like big loans.
RE: HSBC are losing the plot over mortgage lending.... (I FAILED THEIR CREDIT CHECK WTF..?)