hey is anyone else having issues with their ink carts? I bought some that say they are compatible but the printer says they don't work. like they both say canon on them but the numbers are different. so I have an old blk cart and the number is 281, the replacement I bought is blk but the numbers are 251. they look exactly the same except one spot under the bottom, so instead of it being smooth it has like a little sensor underneath. other then that they are the same. does anyone know how to fix this?
