I was going to mention the internet bridge.........but I deleted that part because @Kate seemed to be convinced it was an Extension Kit, hence my response regarding Extension Kit & Wireless Receiver.
@katemag78....... As @what_a_tado said you need a response from Tado Support.
Extension Kit ........is 1 LED
Wireless Receiver.......more than 1 LED
@GrayDav4276 I think the OP is talking about an Internet Bridge
@katemag78 If you have followed the following Tado troubleshooting article and it is still blinking then you will have to wait for support to respond.
@katemag78 Recently my bridge had this problem which I sorted by giving it a direct connection to the router whereas previously connected through ethernet on Power line where it had worked fine for 12 months!!