Sometimes the unit does not use the total amount of water in the water tank. The possible cause can be a blockage in the system.
The machine shows "too hot." Overheating from repeat use can cause this error. To fix this error, allow the unit to rest for 20 minutes.
Sometimes, it won't start brewing because each mode has a specific water limit; It won't work beyond that. You should check that the reservoir is filled or that the water limit is met or not before starting the brewing process.
Sometimes the brewer basket leaks coffee when you remove it because the drip-stop seal isn't correctly positioned. Some waste debris blocks it. Check if there is any waste under the seal. If yes, turn the basket upside down and rinse the basket seal under running water while pressing down on it. This action would remove all obstructing debris.