unbound service fails

[harj]

unbound service stops and I am unable to start it. This has happened couple of times. Happened early in the morning both times. This is the log in the system log

Dec 31 08:06:11	php		/usr/local/www/pfblockerng/pfblockerng.php: The command '/usr/local/sbin/unbound -c /var/unbound/unbound.conf' returned exit code '1', the output was '[1577739971] unbound[16441:0] error: Error for server-cert-file: /var/unbound/unbound_server.pem [1577739971] unbound[16441:0] error: Error in SSL_CTX use_certificate_chain_file crypto error:02001002:system library:fopen:No such file or directory [1577739971] unbound[16441:0] error: and additionally crypto error:20074002:BIO routines:FILE_CTRL:system lib [1577739971] unbound[16441:0] error: and additionally crypto error:140DC002:SSL routines:SSL_CTX_use_certificate_chain_file:system lib [1577739971] unbound[16441:0] fatal error: could not set up remote-control'

This is the log in the DNS log

Dec 31 00:03:45	unbound	959:0	error: failed to read /root.key
Dec 31 00:03:45	unbound	959:0	error: error reading auto-trust-anchor-file: /var/unbound/root.key
Dec 31 00:03:45	unbound	959:0	error: validator: error in trustanchors config
Dec 31 00:03:45	unbound	959:0	error: validator: could not apply configuration settings.
Dec 31 00:03:45	unbound	959:0	error: module init for module validator failed
Dec 31 00:03:45	unbound	959:0	fatal error: failed to setup modules

I have to recreate the root.key file and reboot pfsense for it to work. Please help me troubleshoot why does this happen?

p.s: I have pfblockerng package running.
TIA

[Gertjan]

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