There are few reason that may cause your machine not to grind. Here below some things to check:

1. Check if the Smart Tamping Station is in the correct position: After tamping, return the lever to the at-rest position. Otherwise the machine will recognize that the lever is not correctly positioned: the "Water tank lid" will light ON and the X1 and X2 buttons will start to blink;
2. Please be sure the filter holder is inserted tightly to activate the grinder;
3. A foreign matter has found its way into the coffee grinder. Turn the selector to 15 and remove all beans with a vacuum cleaner, completely emptying and cleaning out the beans hopper.

If the problem persists, please contact customer support.