OnePlus India — about oneplus 3t rear camera focusing

Address:

Surat, Gujarat, 394540

After updating the last version on mobile handset, rear camera focusing has been stopped.
When i have talked with company's customer care they are saying that everyone is facing the same problem.
So i have asked them to replace the rear camera for the handset.
They are saying customer should pay the charges for the replacement.
If it's company fault then why should customer pay the charges.