Happy new year!
According to Npcap, the software is deployed in Windows 10 as a service named "npcap", I suspect the service is not able to restore properly after sleep. You can try and restart this service after windows 10 woke up and see if this could temporarily fix this issue. Also open a bug report with npcap to have some one from their team to look at it. (Sorry, I have a few other things going on and won't have time to handle this in the next a few weeks.)
https://nmap.org/npcap/guide/npcap-devguide.html#npcap-feature-native-servicename
Regarding packet capture alternative, you will be surprised that windows 10 has included its own packet capture tool.
This is a CLI tool called pktmon.exe. I think this is Microsoft's answer to Linux's "tcpdump".
https://betanews.com/2020/05/18/windows-10-secret-network-packet-monitor/
There was a GUI tool developed by Microsoft named "Microsoft Network Monitor". But the tool is no longer supported although you can still download and use it. The tool can open the ".etl" format file captured by "pktmon.exe".
https://www.microsoft.com/en-in/download/details.aspx?id=4865
Cheers!
