Sounds like a faulty box to me - the occasional overnight reboot is perfectly normal, perhaps the odd lockup - but nothing more than that. Oh, and a reboot should take perhaps 5-10 minutes - anything more than that and it's clearly not well.
Either call into report it immediately, or wait here a couple of days for staff to pickup.
Edited to add: rather than make repeated short posts, you have a short time after posting to edit your posts by choosing "post options" in the top-right corner, and "edit post" - that saves several replies to yourself 😉
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