Email that says “one time authentication“? Includes 6 or 7 numbers, what is this?

[LunaTic2019]

I received an Email from Arlo that says “one time authentication code“?
In the email it had a code that included about 6 or 7 numbers.
I’m just trying to figure out what this would be about.
When I go to recordings on the day I received the email, there are only 6 recordings from the whole day where typically there are 100+ recordings. My Arlo system has been installed for more than a year.

[jguerdat]

The one time authentication email is due to use of 2FA on an untrusted device (typically a computer). Do you have 2FA set up? Are all devices that use the app set as trusted? As yet, a computer isn't trusted so all use of it will cause that email (which can be changed to a text if you wish in the 2FA settings). 

This wouldn't have anything to do with the number of recordings. Do you happen to have a filter set in the library?