One of our door sensors has been eating batteries at an increasing frequency

Over the past year or so, one of our door sensors has been eating batteries at an increasing rate.  We received the Low Battery message again the other day and it was only just over a week since we last replaced it. The time before was at about 2 weeks.  My husband has a battery tester and he has been testing the New batteries, before installing and it shows a 100% charge and the Old batteries he removes are indicating LOW charge.

The last time we got the Error Message, I went through the tediously time consuming process, digging and trying to find a solution, before I finally was offered the option for a CALL BACK from a Home Security Technician. After his questions, our explanations and answers, he did some remote troubleshooting and determined our Door Sensor is FAULTY and needs to be replaced.

Since then I have been trying to determine how to request a self-replacement kit which will include the new door sensor and instructions for installation.

Is this something that you can help us with?