The reason is that the host node runs out of resources and shuts down your VPS. If you want, we will transfer you to a less loaded node so that it doesn't happen again.
The shutdowns might be caused by the high load on the node itself. If you would like we can recreate your service on another node however, all the data will be lost.
Let us know if you wish us to proceed with this.
David Filipov
AlphaVPS Team
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