Ps2 controller losing connection

Hello: I purchased a ps2 controller in July, which worked great until the last event I used it in august. I installed it in an R2D2 robot I built.
The controller worked great and I had no problems with it during the initial build and the 2 months that I used it.
I tried to use it this weekend and the controller continually loses sync with the receiver. The receiver’s red light flashes and both the red and green lights flash on the controller, and then it will regain sync and operate again for awhile. It loses sync about every 10 seconds although at random times. This is within a 5 foot range.
It has been stored all winter inside my heated home.
I changed the controller batteries with new ones and made sure the robots batteries were fully charged.
I made no changes to the robot over the winter, and as I understand it the controller and receiver should stay in sync no matter what the software code on the robot is doing.
Any advice would be greatly appreciated.
I also tried the robot in my home and at an event, so do not assume there was any odd interference problems. And in fact nothing has changed inside my home either.
order # 103550
Customer 163329
-Thank you
-Stampee

There is no way to know what happened if it is now broken. Static electricity… who knows?

umm… that is what I am trying to determine. is it broken or what? It works sometimes, then loses sync.
What is the warranty on this product?
-Stampee