Samsung — Samsung galaxy m31s mobile

I purchased Samsung m31s mobile 1-1/2 year back. After recent update it started getting hanged and autorestart was happening. At last it got hanged and was showing only Samsung logo and not going further. Now phone is dead. When went to Samsung service center, i was told that this is the issue faced by large number of customers of this model and need to replace motherboard which is very costly. My very important data is there in mobile and service center is saying it is not possible to retrieve the same. When same storage is still there in mobile, data retrieving should be possible but service center not ready to help. Moreover if the issue is faced by large number of customers, then it is manufacturing defect or defective update and Samsung should come forward on their own and help customers by offering free replacement of motherboard and free retrieval of data as a goodwill gesture to maintain their status in Indian market.