Caffeo Solo brewing unit error

Hello,
I had a problem while using the cleaning process ( the one for the brewing unit, not the descaler), the brewing unit stuck in the engaged position so it was not possible to extract.
I tried a few things and finally opened the machine ( something I had already done on a Caffeo Solo & Perfect Milk with success) to reset manually the brewing unit by disengaging the motor.
I managed to do that and manipulated the motor quite a bit before finding the correct position again.
Now the problem :
The machine can brew only one cup before having a problem and shutting down ( displaying the coffee beans blinking in sequence before the shut down). I then have to restart it while pressing the one cup and two cups buttons before being able to make another cup of coffee.
Does anyone have an idea ?
I was thinking maybe a bit of grease in the gears ?

Thanks a lot for any help !