Xfinity WiFi extender model XE2-SG - incompatible or needing a reset

My extender was working just fine. I added a Xfinity xPro extender along with the new gateway that comes with it. Now, my XE2 extender will no longer connect. I keep getting a very slow blinking white light. I've tried unplugging, deleting from Xfinity App, rebooting gateway - nothing helps. Can this extender be factory reset, or is it not compatible with the new gateway, or is it broken? I tried the Xfinity chat service for help too. Any thoughts please?