Creation of Lambda failing

Trying to create a lambda. But getting the following error on execution and I am not able to identify the root cause.
Error creating Lambda function: ValidationException:

[ status code: 400, request id: 8472bfb4-ecfa-4dfa-b7f4-7178c5836336

resource “aws_lambda_function” “test_lambda” {
s3_bucket = “https://”""
s3_key = “”
function_name = var.aws_function_name
role = “arn:aws:iam::123456789:role/handler-role”
handler = “test::test.Function::FunctionHandler”
runtime = "dotnetcore2.1

I’ve got the same error, and deployment is proceed from zip file for Python3.8 function. Function is packed with all dependencies and I tried to upload it manually via AWS consol and It worked there.

How to increase verbosity on such type of errors (nothing I could see when TF_LOG=TRACE)? It takes a huge amount of time pondering in the dark with a torch to find the source of the problem.