I have bought it twice because I thought it was just a problem the first time. The battery does not work and does not even charge. It is useless

The battery, although it appears to be original, is difficult to insert and in practice, it does not charge above 94%. As soon as it drops below 39%, the phone shuts off. I had to put the old battery back because it cannot completely shut down at 39%. Money wasted

I bought it thinking it was genuine. The markings on it were the same as the genuine one, but the performance was very poor. I can say that I didn't notice any difference in duration compared to the one I had before, which was 2.5 years old. After 4 months, the performance has drastically decreased. The capacity, as measured by an app, is 2290 mAh.

Once again, a battery of very good quality... It constantly shuts down my phone and I am forced to put back its own battery.

Purchased on 22/11/2021. From the moment I put it on, the AccuBattery app showed it at 60% health. That's what it showed on my mom's battery before replacing it. Unacceptable product. Although externally it had the same markings as my mom's battery (it looked genuine), even the manufacturing date written on it was very recent (within 2021). I have reached the point of having to charge it 2 or 3 times a day, which is tragic, especially for this particular phone that had a nuclear battery from day 1. Even the previous one lasted longer than this thing now. What a waste of effort.

UPDATE 21/04/2022
the situation with this specific battery was unbearable, so I replaced it. Upon opening it, I see a swollen battery (at least 15-20% of its volume) and the charging cable passing over it was about to disconnect. Guys, BE CAREFUL and stay away from this "genuine" battery.

Obviously, the battery's measuring chip does not accurately send the remaining battery life, resulting in it quickly dropping from 60% to 10% and then lasting for several hours. Overall, it retains almost 80% of the original.

It lasted for 2 weeks. We expected more than that.
Personally, my phone was useless because I didn't have a battery to replace.
At first, I bought this one and... battery health was only 23% after 1 week!
And it even swelled.
After a lot of searching in stores and dealerships,
I got a Cameron sino and I was saved, a 1-month battery with 97% health.
(I'm writing this so that someone can save their phone from the trash because there are no batteries for this model anywhere and the ones that exist are from 2020 or older.)

(+)Quite good, good performance like the first battery, lasts a day with sufficient use.
(-)It heats up somewhat easily, I would say.

Quality and affordable solution, I changed the original battery after 2 years because it swelled.
(Transferred in a simple envelope but wrapped quite well for protection)

Update 10/2022, it has been working exceptionally for almost 1 and a half years, its performance has definitely decreased, it lasts me a day with regular use, but for a product that is "authentic," it kept the phone alive. The Poco F1, after 3 years, does not lose at all to the current ones and is a tough nut with the processor it has. It's a shame to throw it away for a battery. Luckily, unlike others, the battery doesn't seem to be problematic for me

The battery played up after two weeks of use, of course from the beginning its performance was not corresponding to its description. According to my research and experience, it has a capacity of around 2300mAh and not 4000mAh as stated.
P.S. My device was destroyed by the battery swelling, now it needs a new charging board!

It didn't turn out well for me (battery health 78%) even though it's new... purchased from a good store on Skroutz and cheap.

Authentic battery.