That's pretty crap service - and not great the battery failing after only 2.5 years
Lots of lead/acid batteries fail soon after the warranty expires. Nothing new there. Modern battery chemistry is not kind for situations where the battery is not kept fully charged at all times. Every discharge and recharge cyle adds up.
The factory 12V batteries on the I-5 are a well known weak link. Mine is coming up to two years old. I’ve never used the blue link app but often used to play the radio while parked - often until the car warned of auto shut-down.
Blue link has created a problem for some, at times, where the system keeps getting activated unnecessarily, multiple times. Leaving the car at below 20% state of charge, for the traction battery, was another reason for a flat battery (they now apparently recharge the 12V battery until 10% SOC). Dash cams, which don’t completely shut down, are just one more possibility for a parasitic load with the car off.
Mine was like one of these. Plenty of options with a search on epay for 12V battery monitor. I bought four at the time - one for each car battery and two for monitoring the batteries which run my chinese diesel heaters.
https://www.ebay.co.uk/itm/315693335365 ... R6L4_dSzZA
If the battery proves to be dead and is the only reason for the fault, I would be changing it soonest.