Card issuers are paying attention to a number of different factors to predict cardholder risk now. If you're deemed a high risk, it could push your rates up.

Hardekofp says the following are other factors that could affect your rates:

Your credit score is low or was lowered recently. 

You balance is too close to your credit limit on your card or other cards -- even if it was the issuer who lowered your limit and caused your balance to be closer to your limit.

Many card issuers still give themselves the right to change rates at any time for any reason. Read your contract. "Any time for any reason." Sometimes it's random, but sometimes it could actually be for a legitimate reason like economic market conditions.

Hardekofp suggests asking your card issuer to lower your rate. If it doesn't work, continue building a good payment history and credit score and ask again. It never hurts to ask.