PHEV Won't Charge to Capacity

2018 PHEV bought 3 months ago (new). Initially, it charged to 24 miles. For the last week it now only charges to 14 miles no matter how long I leave it plugged in (even 2 days same result). Brought to dealership, service manager has absolutely no idea about PHEV, kept talking about hybrid capability. He charged for 24 hours, showed 22 miles, though before I left garage it dropped down to 15 miles (less than 30 seconds). Help, any ideas? Thanks.....

Could be just down to differences in air temperature. The estimate takes that into account and varies wildly as a result. If your dealer had the car inside and got that reading, and it plummeted as soon as you left, it would explain it.

If you are using the Guessometer (range indication), this is wholly unreiable to indicate the state of charge/health of the battery. As the previous poster, the circumstances of driving make the range of the ca fluctuate wildly.

Turning the airco on will also reduce the range shown on the guessometer.