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How to Fix Bootloop — Ulefone Armor 21
How to Fix Bootloop — Ulefone Armor 21
The Ulefone Armor 21 is a 2023 Android 13 smartphone powered by the Mediatek Helio G99 (6 nm) with 8GB and 256GB internal storage. It features a 6.6", IPS LCD, 120Hz, 1080.0x2408.0 display and is available in Black.
The Armor 21 is equipped with a Li-Po 9600 mAh, a 64 MP, 4K@30fps, 1080p@30fps main camera, a 16 MP, 1080p@30fps front camera. The device uses a Nano-SIM + Nano-SIM configuration. It weighs 400 g.
A bootloop on the Ulefone Armor 21 occurs when the device repeatedly restarts without fully loading Android. This is commonly caused by a failed software update, corrupted system files, or an incompatible app. Most bootloops can be resolved without losing data by clearing the cache partition first before attempting a factory reset.
Factory reset may be needed as a last resort — erases all data.
On your Ulefone Armor 21: force restart: hold Power for 15–30 seconds
If still looping: enter Recovery Mode
Navigate to 'Wipe cache partition' → confirm → reboot
If still looping: return to Recovery
Select 'Wipe data/factory reset' → confirm (erases all data)
Last resort: use your manufacturer's PC tool to reinstall firmware
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