If your pump has delivered 50% of your Total Daily Insulin over the previous 2 hours, you will get this alert. Basal insulin delivery will be stopped until this is no longer true.
You should tap OK and confirm that your Total Daily Insulin amount is correct in the Control-IQ menu. During this time, you will still be able to manually bolus for food.
Tandem handles issues with the connection between your Dexcom transmitter and t:slim X2 pump, questions about calibration, the “---” display, and sensor failures after the 2-hour warmup period. To report a sensor failure after the 2-hour warmup period, visit tandemdiabetes.com/G6Form
For all other CGM issues, including sensor failures during the 2-hour warmup, “no restarts” alert, or physical problems with your sensor or transmitter, such as bleeding, bruising, skin reaction, adhesive issues, applicator issues, or broken wires, you should contact Dexcom using one of the options at dexcom.com/contact.