Your DHCP log shows that only four clients successfully requested an IPv4 address:
55417:Nov 7 15:06:41 dnsmasq-dhcp[14377]: 931615095 DHCPACK(wlan0) 192.168.0.73
61372:Nov 7 15:28:01 dnsmasq-dhcp[14377]: 915842021 DHCPACK(wlan0) 192.168.0.107
61586:Nov 7 15:29:07 dnsmasq-dhcp[14377]: 3662234458 DHCPACK(wlan0) 192.168.0.30
64158:Nov 7 15:41:22 dnsmasq-dhcp[14377]: 3249465666 DHCPACK(wlan0) 192.168.0.136
Does that fit the number of clients on your network?
What client did you use to monitor your Pi-hole's connectivity?
Is it among the clients that requested a lease?
Also, your log doesn't show any DHCP activity between 15:47:43 (line 65178) and 15:49:27 (line 65362). Do the lines in between contain any hints to a possible cause?
If you want to upload the complete log without making it public here, you can do so by executing:
cat /var/log/pihole.log | pihole tricorder
or substitute with any relevant other file, and then post the token(s) here.
(see also How do I debug my Pi-hole installation? for other ways - apologies for not mentioning this earlier).