OMV 4.1.10 and Letsencrypt Plugin

So I had been running OMV on my RaspberryPi3 out of necessity for awhile now (several months) and yesterday I picked up a Q8300/8gb ram and I decided to install on that and use it instead. Previously I'd had Letsencrypt running on it without issue and installing seemed pretty straight forward. Well this time it's crapping out and I'm suspecting its because the certificate won't authenticate where I already had it setup with the old server. I'm getting something like this on generate.

Command: export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C; /usr/bin/certbot certonly --non-interactive --test-cert --rsa-key-size 2048 --text --keep-until-expiring --agree-tos --allow-subset-of-names --cert-name angmcd.ddns.net --email gpeverill@gmail.com --webroot -w / -d angmcd.ddns.net 2>&1

Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator webroot, Installer None
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for angmcd.ddns.net
Using the webroot path / for all unmatched domains.
Waiting for verification...
Challenge failed for domain angmcd.ddns.net
Cleaning up challenges
Challenges failed for all domains
Done...

Ideas? I still have access to the RaspberryPi and the /etc/letencrypt.

Thank you that helped after changing webroot it was almost good to go. I created the cert. it went through and I was all good! that is until I realized that I frigging created a test cert (I had accidentally turned on the switch while noodling around). Now it complains the cert is still valid (which it still would be):

Command: export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C; /usr/bin/certbot certonly --non-interactive --rsa-key-size 2048 --text --keep-until-expiring --agree-tos --allow-subset-of-names --cert-name angmcd.ddns.net --email gpeverill@gmail.com --webroot -w /var/www/openmediavault -d angmcd.ddns.net 2>&1
Cert exists: 1


Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator webroot, Installer None
Cert not yet due for renewal
Keeping the existing certificate


-------------------------------------------------------------------------------
Certificate not yet due for renewal; no action taken.
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What would be the easiest way to do this? revoke the cert on the other machine using something like..

certbot revoke --cert-path /PATH/TO/cert.pem --key-path /PATH/TO/key.pem

on the raspberry pi with the old OMV install with the working letsencrypt?