Hey there, Puteriyasir!
Thanks so much for using Apple Support Communities.
Being able to take great quality photos is really important. If you're experiencing this issue after seeing some physical damage on the iPhone, then bringing it in for inspection is likely going to be the best option. Service options can vary around the globe but if you have options for service in your area, it's a good idea to let the experts diagnose exactly what is going on and provide you with a clear path to get it taken care of.
You can learn more here: iPhone Repair and Service
If you decide to set up service, you can do that by reaching out here: Contact Apple Support
We hope that this information is helpful.
Have a great day!