Insignia Key Battery Low Warning

Oh my goodness, that sounds awfully familiar! I had something very much like that happen with my Insignia. Were you able to use the spare key, or did it act the same?

Spare key exhibits the same symptoms. Any specific recommendations for battery replacement, or further diagnostics?

Because nothing changed with the spare key, I'm thinking you might be on the right track with the battery. I had a go at replacing it myself, but without success. Eventually I had the dealer take a look. I'd really recommend heading to a workshop, just to be sure.

Confirmed, replacing the battery in both key fobs resolved the issue. Total cost: 37€. Thanks for the advice.