Garmin GPS watches crashing, stuck in triangle 'reboot loop'

Garmin users across multiple watch lines (Descent, Forerunner, Epix, Fenix, Instinct, Tactix, Vivoactive, Venu) are experiencing crashes and persistent reboot loops showing a blue triangle, which Garmin has acknowledged and advised addressing via power cycling, syncing with Garmin Connect/Express, or factory reset (with potential data loss). The suspected cause is a faulty firmware update affecting GPS, though Garmin has not confirmed the root cause; a past 2020 WastedLocker ransomware incident is mentioned as historical context.