I bought a180,20000 charging treasure in a physical store. After using it that night, I found that my mobile phone could only be charged three times, and I didn't change it when I went to the physical

I bought a180,20000 charging treasure in a physical store. After using it that night, I found that my mobile phone could only be charged three times, and I didn't change it when I went to the physical store. What should I do? The rated capacity of a 20000 mA charging treasure is about 12580 mA. It is recommended to check the battery capacity of the mobile phone. For example, if the battery capacity of a mobile phone is 4000 mA, and it can be charged for three times from 0% to 100% each time, then there is no big problem with the charging treasure. On the other hand, the capacity of the charging treasure is a virtual standard, and you can find a merchant to return it. If the merchants do not agree, they can call the local consumer association or call 123 15 to defend their rights.