If your Keurig is spewing coffee grounds in your cup, it means that the coffee grounds have made their way into the dripping needle of the machine. You will need to clean this needle by removing it and following the cleaning instructions mentioned in your coffee maker’s manual. Once you are done, start the machine to brew just some water to see if the grounds are still coming out. If they are, repeat the water-only brews to ensure that there is no residue in the needle. You should also descale your brewer every once in a while to prevent this from happening.