Hello I will help you with your question,
The sensors may have been damaged during the changover. If the shop has a sensor tool they should be able to read the sensor data from each wheel sensor to see if they are functional. If all sensors work then they only need to be registered to the vehicle or there is a fault in the vehicle but the fault is more likely in the wheel sensors.
If your shop does not have a sensor tool most of the large tire stores do, these are expensive so not every shop will have one but if you do tire work on anything newer than 2008 vehicles it is a must have tool.
Let me know what i can do to help you with this
Are you saying that the sensor must have been broken at the change over since they worked for two winters? Are you sure these wheels have a sensor?
Did you replace the wheels this year?
If you did you need a set of sensors to install to these wheels. The sensor is part of the valve stem and would have had to be transfered from your original wheels to these or a new set of sensors installed to these wheels and registered to the vehicle.
Many people don't bother with the sensors in their winter wheels and just have the light on all winter. They check the air pressure every week or two to be sure they didn't pick up a nail or screw.
Let me know if these are the same wheels you rant the last two winters
Then the sensors should be in the wheels and one may have been damaged installing the tires. A good tire shop can read the sensors and find out if all are transmitting and replace one if it was damaged.