I have the same issue.

Thanks for the tip on deleting/re-adding profiles to get insights working again, will keep monitoring here too.

If it's DHCP lease renewal related then perhaps it can be worked around by reserving IP address per device in the DHCP server?

Not ideal I know, but something at least until it's fixed to become profile or MAC based rather than IP based (if that's the issue)...

Also apologies for seeing this only now...seems the forum web admins have been tinkering with the forum URL so that .../en/... can sometimes be .../us/... which doesn't connect correctly with a user's forum profile outside the US.

Anyway to clarify (I hope), Insights will happily log away for a day then show 'No History', fixed only by a router reboot or deleting/re-adding profile.

I've not been able to troubleshoot longer than a day because the router won't stay WAN connected for much longer than a day...because of https://community.tp-link.com/en/home/forum/topic/223016