Can someone help me to reset the system code as tenants did not give it to previous owner.

Any reason to PM me then ask twice in the same forum for the same answer.

NO

Read previous thread, Dont duplicate

Pay someone to sort it as recommended, the only ting you will get from the manufacturer is the default codes, which they probably won't be anyway.

Other option, don't use it.

thanks all, Sorry Alarm should have waited for you response.

No, you should have posted in open forum. Not Private messaged me.
That is basic courtesy in any forum when it is your first post.
However the answer as you can see is the same.

Most and myself with some professionalism and self respect will never give defaulting information on an open forum.
This is for your and others protection. Also debated to death here and other places.

To make it simple for those that have difficulty understanding this, if you were "casing" somewhere and had access in the unset mode you could use this information for criminal gain.
We are not here to give that opportunity.

Simples