Smart Powerbank 20000

Good day

I received my smart powerbank and used it, BUT it only charges my Note 10 one time...(it shows between 25 and 50%, but then when i use it again it dies on me)

Im sure that it is NOT 20000 power - as advertise in your add !! I am not happy with it - This is the 1st time i bought something from you..

I have already used and charged it 3 times, (Thought it would make difference after 3 x charges) But still it looks like a 5000 to 7ooo power bank