Solid red LED on bootup

Got my ruuvitag several months ago and just now trying it out. When I connect the battery all I see is a solid red LED. Does anyone know what that means?

It is possible that the unit is defective but to make sure, try to flash a new firmware:

@lauri I can’t even get the tag to come up in the bluetooth list.

By keeping B pressed while pressing R?

If not, the unit is most probably faulty. Please contact to get it replaced/fixed.

Yes tried that also. Will contact sales to get a replacement. Thanks!

Did you try battery removal and exchange with another battery?