Powercore 20100 not fully charging

Powercore 20100 not fully charging. Reaches 4 leds and keeps blinking last led. More than 24 hours using a “WCP01 USB-C PD 3.0 Wall Charger - Tronsmart” and a Manhattan 353311 Hi-Speed USB C Cable- C Male To Micro B Male. And never reaches full charging and turn lights off.

Also charges a 4000 mah 3 times only. Is this the expected efficiency ?

It is PowerCore 20100 model A1271, right? Please charge it with a standard 5V wall charger, like an iPad charger, via the supplied Micro USB cable.

Generally speaking, the external battery is normally capable of a 60%-70% charge transfer of its capacity depending on the internal resistance of the USB cable. Approximately 30-40% of the battery capacity is unable to be used because of efficiency problems that affect all electronics devices. These include power lost from circuit heat and voltage conversions from the battery, the charging cable, and your device. Therefore, it is normal that the PowerCore 20100 offers about 3 charges to a 4000mAh phone.

If there are other questions, please reach support@anker.com for help.

The Tronsmart is 5V 3A. I bought it because I was told to use a charger greater than 2 A. I already used an original Samsung 2 A charger and it never finishes charging as well.