Reflection falling below 4%

I have 2 Garadget’s over a year now. Front garage reflection has always been 90% or more. However my back garage has been sending false opening and closing notifications the last 2 weeks. Today it’s off the charts. I tried switching the reflective tape and no help, slightly better in the dark but hovering around 6-7%. After reading the other Posts regarding weak reflections, I’m pretty sure my laser is loosing it’s mojo.
How can I order one and does it require any calibrations if I were to replace it?

There is no need for calibration because Garadget does that continuously in the software. For instructions on replacing the laser at home, please see this post: