Bitnami Joomla strange url in user registration email

[chizuoka]

I have a Joomla installation on Bitnami with J2store.

I was testing making a purchase and got a weird account detail email url after registering before making purchase. It has a url9680.mydomain.com.

What is that url9680 subdomain and who generates this? J2store says it’s not them? Also it has some weird parameter being sent over as well.

This is the content of the account details email

———————————————————————————-

Hello William Tell,

Thank you for registering at XXX.

You may now log in to http://url9680.{mydomain}.com/ls/click?upn=hpceFv8zuOprnK7VKrl0g5kYsXtg4x07y2Se250I39U-3D4ow__XeYEJ883fpoHW3bZ9x5B-2Bkr1T9JYsA-2FtVS5QUqZGMc8wzK1llTEWcsE9M1QX6RH8eptrtMj2oqgy4w6Qa6lxQCgbJIvXJroIlRCV2yaXtzPwh3Xh4S2LtWoppfp-2F6UO26eIHhRAciXtJWqEcek4xkyQwzXp-2BpKMLahkivPGC-2FgNGcxTE-2FvM-2FZEA3bl4V-2F5VaOHTPTUlMW0HhT9m86PTFiA-3D-3D using the following details:

Username: [email protected]

Please do not respond to this message. It is automatically generated and is for information purposes only.

[zzella]

If you go to http://url9680.{mydomain}.com does it resolve? Try other random subdomains also eg abc.{mydomain}.com. Does it load your site under that url?
If your server is configured to serve up your website using any subdomain that could be the issue, especially if that email template gets generated and stored in a cache. It may be getting generated while the website is being browsed using the http://url9680.{mydomain}.com url and then reused later.
This may not be your issue but I had a similar problem with unrecognized subdomains appearing on my Joomla site and they were coming from the Joomla cache. There was some kind of crawler constantly accessing our site using different subdomains which was filling up the cache with incorrect urls.
Solution for us was to redirect all subdomains to the main domain using DNS. Something similar may work for you (then clear your cache and try again).
Curious if others have insight on this as it would probably help us too.