Stuck in anti theft mode

Here is a guide that will get us started. Take a look at this and let me know what happens with this.

https://www.2carpros.com/articles/how-to-reset-a-security-system

Also, I attached the info from the manual below on how to disable the system.

Lastly, is there a history to this? In other words, how did this start? If it just started one day we need to check both grounds shown in the wiring diagrams. Let me know what questions you have and what you find with this. Thanks