New cell phone battery broken again?

I would be so grateful if you could help me. I noticed a week ago that my mobile phone battery (huawei p10 lite) has broken. He unloaded within 1 hour and then recharged to 100% within a few minutes. Then I bought an original Huawei battery for my model and installed it today - the problem is, it discharges exactly the same speed again. I'm desperate because it took me 2 hours to install it. Could anyone who helped me out, WHAT? COULD THE PROBLEM BE?! New battery also broken (by chance)? Or does it have to do with my mobile?

Have you ever completely set to factory settings?

Did you close all background apps?

It may be that some apps, or programs still work in the background and therefore your battery can quickly discharge.

Let a cell phone look best in a Saturn or media market, by a technician.

No I did not! Should I try that?

I have closed everything that goes only. Even some apps are inactive, so the content is only updated when I open it! Is there anything more to be done somewhere?

So that's always the first option 😁

Did you update your phone?

So factory setting and then all update.