Hello Stephen!
I have the same problem with Fun Tec. I have my own domain and I don’t think it is the problem of letsencrypt. Here is my logs after command sudo ./launcher restart app. Can you find some useful information?
Shutting Down
run-parts: executing /etc/runit/3.d/01-nginx
ok: down: nginx: 0s, normally up, want up
run-parts: executing /etc/runit/3.d/02-unicorn
(2165) exiting
ok: down: unicorn: 1s, normally up
run-parts: executing /etc/runit/3.d/10-redis
ok: down: redis: 0s, normally up
run-parts: executing /etc/runit/3.d/99-postgres
ok: down: postgres: 0s, normally up
ok: down: nginx: 2s, normally up
ok: down: postgres: 0s, normally up
ok: down: redis: 1s, normally up
ok: down: unicorn: 2s, normally up
ok: down: cron: 0s, normally up
ok: down: rsyslog: 0s, normally up
run-parts: executing /etc/runit/1.d/00-ensure-links
run-parts: executing /etc/runit/1.d/00-fix-var-logs
run-parts: executing /etc/runit/1.d/01-cleanup-web-pids
run-parts: executing /etc/runit/1.d/anacron
run-parts: executing /etc/runit/1.d/cleanup-pids
Cleaning stale PID files
run-parts: executing /etc/runit/1.d/copy-env
run-parts: executing /etc/runit/1.d/letsencrypt
[Wed 16 Dec 2020 01:26:10 PM UTC] Using CA: https://acme-v02.api.letsencrypt.org/directory
[Wed 16 Dec 2020 01:26:10 PM UTC] Single domain='a.mapengfei.xyz'
[Wed 16 Dec 2020 01:26:10 PM UTC] Getting domain auth token for each domain