[Ultimaker 2 pausing halfway a print?]

Hello,

Recently we're having a problem printing a large part.

The print is started at the end of the day. When I come back the next morning it is just paused.

It's an 8 hour print. The first time it stopped after about 2 hours, the last time it was about 3 hours.

Does anyone have any clues what I could check, or what could be the problem?

Small parts work just like fine.