<I am trying to save model class data in DB using ...

# stackoverflow

[user]

I am trying to save model class data in DB using Spring with Kotlin but I am getting exception
I am learning Spring with Kotlin and I am getting below exceptions while saving data in the local Database
My Rest Controller looks like below
@RestController
class MarketPlaceController(val service: MessageService) {

@GetMapping("/homepage")
fun getHomePage() = "NFTs Marketplace"

@GetMapping("/errorpage")
fun getErrorPage() = "This is error"

private var NFTs = mutableListOf(
Message(1, "Title #1", "Description #1"),
Message(2, "Sneaky Vampire Syndicate", "Description #2"),...