OnePlus India — Mobile repairing

Address:

One Plus seawoood Grand Central

I'm Ganesh Deshmukh and I'm using One plus 8, on 15 aug mobile is stop working automatically and switch off and not able to restart, nothing is working I'm going to service centre but deo 15 aug service centre is closed and I'm going to other mobile repairing shop mobile is out of warranty so I ask to check what's happening he said may be hardware issue then I leave and next day mobile submitted to service centre the service centre is saying mobile motherboard is not working needs to replace and cost is 28000 and i said i don't want to replace and I'm going to again yesterday mobile repairing shop and ask to repair the mobile and cost is 2500 he repaired and issue is resolved not any motherboard issue is found.
Service centre at Seawoood Grand Central Navi Mumbai.
On mobile screenshot attached for reference.