Why there is no battery charging icon indicated on my phone when I plug it to the charger?

If the battery hasn’t been used for long time, it’s possible that the battery had been over discharged. In this case, the phone would have no charging indicator when you plug it to the charger, which doesn't mean the battery is broken. You can charge it for at least 10-30 minutes and see if there is anything changing. If the same symptom persists, the battery may really failure. You need to send it to our repair center.
You can find the contact information of our repair centers from the following website: https://www.tcl.com/global/en/support-mobile

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