onOpen event is being triggered randomly by many fake users

Question

I have a Google Docs Add-on and when the onOpen event happens it registers a new user on our database. The email of those users appears to be faked and autogenerated...e.g. the first names will be the same and the last names will be something else like "[email protected]" and "[email protected]" and a lot of them also have 3 or 4 letter digits at the end of their name "[email protected]". Almost all of them have gmail addresses though it's hard to be for certain since it is a small add-on and there's a mix of real users. The faked users only seem to running the onOpen trigger and that's it. They don't actually do anything else in the app. I'm talking hundreds of them over the past couple of days. How do I prevent these users from accessing my Add-on? The script is not public (that I know of but I'm not sure how to check that). My script executions look like this:

—   onOpen  Simple Trigger  Nov 12, 2023, 4:38:06 PM    0.502 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:36:47 PM    0.506 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:36:36 PM    0.823 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:34:20 PM    0.651 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:33:27 PM    0.59 s  
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:30:48 PM    0.723 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:28:57 PM    0.5 s   
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:28:51 PM    0.469 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:28:40 PM    0.558 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:28:35 PM    0.505 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:21:08 PM    0.693 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:16:18 PM    0.481 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:14:31 PM    1.332 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:13:58 PM    0.521 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:12:18 PM    0.511 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:09:19 PM    0.469 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:03:59 PM    0.477 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:03:06 PM    0.74 s  
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 4:03:03 PM    0.48 s  
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 3:48:43 PM    0.46 s  
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 3:48:40 PM    0.661 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 3:43:44 PM    0.453 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 3:42:57 PM    0.731 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 3:42:24 PM    0.708 s 
Completed
—   onOpen  Simple Trigger  Nov 12, 2023, 3:42:12 PM    0.415 s 
Completed