No. Unlike with a Dexcom G5 Mobile sensor, a Dexcom G6 sensor has a mandatory shutoff at 10 days, after which it cannot be used.
Important note about Dexcom support:
Dexcom and Tandem have agreed which system issues are best handled by each company, including which company is responsible for reporting those events to the appropriate regulatory authority. To help ensure that the required reporting takes place in a timely fashion, customers may need to contact Dexcom for some issues and Tandem for others.
Tandem handles issues such as loss of connection (on pump only) and the invalid transmitter (Alert 29) on pump only.
For all other CGM issues, including would not accept calibration, the sensor failure 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.