My daughter has had T1D for 6 years now. We use a Medtronic 670G without a CGM. We have had multiple "!Testing Error" warnings on the Contour BG meter. Ascensia has given us several replacements and the error continues. We do not use expired strips, our strips pass the QC, the alarm occurs for my daughter at times, and for my wife and I when we are doing checks in the night as well. Good technique is used at all times. Our diabetes educator, Ascensia, and our Medtronic contact people all say "We have never seen that alarm before". FYI - We did a Self Test on the 670G insulin pump and it showed an error code and Medtronic sent us a new one. We set up the new one and the error is continuing. With it continuing despite several new meters and a new pump, what should we do next? Has anyone ever seen this error before? We are trying strips from different sources, paying particular attention to how we store them, etc. We are frustrated because we are right back where we started after all this effort.