While it makes it look like your cash register is displaying PEA, it is actually displaying PER. PER means Paper End Receipt, which means your paper roll has run out and the little sensor in the front of the receipt printer can’t detect any paper and will display PER until the paper roll is replaced. Once you replace the roll, press clear and this will clear the error.

If you have a fresh paper roll and the paper is fed correctly through the front and you still get the PEA error, you might have a broken sensor. The sensor can be cleaned with a lint free cloth. If that doesn’t work, then the whole printer mechanism may need replacing.