iPhone camera stopped working

Hello, i have a question, I don’t know where else should I ask. So the problem is, that one week ago my Iphone camera randomly stop to work and face ID with flashlight also doesn’t work, I though  it’s because of the new iOs 14.6 update, but in store where I bought a phone they told me that’s not because of that. So my warranty expired 6 months ago so for all the checks and repairs I have to pay. So the question is, if it’s happened like this, some things randomly stops to work, there is any place where should I contact?  Or all the responsibilities it’s on me?  Because previous iphone I had for more than 3 years and it was working really well after that 3 years, with this phone I’m only 1 and half year, and thats what happened, especially when the technical problems came from nowhere, so it’s very sad.

Thank you for your time 🙏  

[Re-Titled by Moderator]