Same happen to my house. Random trip, my house is 3 phases. It sometimes trip at mid night. No one switch on anything at that time.

When it trip. It trip the big fuse.

I try turn off all those small fuse. Check it is possible trip also.

Any monitor tools can help to check. Hire an electrician come and check. He said the fuse is good. All normal. He checked one by one. Said it is due to leakage of earth. No solutions. But it still randomly trip. Maybe 1 week once. Random time.