When unlocking my car the alarm will sound and does not stop for about three minutes

Are you unlocking the door with the metal key or are you using the key fob? If you are using the metal key then this is normal. You need to deactivate the alarm prior to opening the door. What happens is, someone could get a metal key cut to the vehicle and just unlock the door so we need to unlock it with using a fob button.

So let's check for codes because I suspect you will have a code in there pointing to a key issue which means we will need to have new keys programmed to the vehicle.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Let me know if you have questions. Thanks

The alarm will sound when I unlock the car with the key fob or the metal key it will not turn off even if i start the car. After about 3 minutes it will turn off by itself but the lights will continue to flash.

Okay. Let's scan for codes because I am sure we will have some codes that will tell us what is happening. This is an active security event and we will get some codes that tell us why.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing