Chase doesn’t want to honor an old promotion promising to lock in a customer’s APR until their balance is paid off, so they’re just ignoring the original terms and jacking up interest rates. The bank wants to hike a promised 3.99% rate to either 7.99%, or 5% of the total balance plus a $10 monthly service charge, terms that are dull enough to put you to sleep until you receive the next month’s bill. Inside, Credit Slips walks us through how this is legal, along with tips for recapturing the stolen promotional rate.