Atomstack A48 alarm1

Hi Guys !!!
I have a new laser and I’m having trouble installing it.
The installation went well at first, autoguiding, focus!! Didn’t try to engrave.
Then I turned off the machine. Then about an hour later, I came back to set up the camera. I could see the image for a moment then nothing and that’s when I got the first error message…

It’ Atomstack A48 and I have this error message:
ALARM:1

Limite stricte déclenchée. La position de la machine est probablement perdue en raison d’un arrêt soudain et immédiat. Un nouvel autoguidage est fortement recommandé.

Grbl C10-0130-V1003 [‘$’ for help]

[MSG:Check limits]

[MSG:‘$H’|‘$X’ to unlock]

[MSG:Caution: Unlocked]

I redid all the connections, reset the machine, it doesn’t change anything.
someone to help me please?!
Thanks a lot

Delphine from France… English not good sorry