Meterpreter Dying?

I was playing around with meterpreter and turned off protections on a windows vm then ran the exploit (windows/x64/meterpreter/reverse tcp). After practicing using all the different functions in meterpreter for a long while the shell suddenly died. I turned persistence on before then, but that just stopped working.

* Started reverse TCP handler on xxxxx

* Sending stage (206403 bytes) to xxxxx

* xxxxxx - Meterpreter session 4 closed. Reason: Died

It just kept going like that every 5 seconds. Any ideas why?