IIS Webservice - Need to Accept raw JSON from Stripe WebHook

Job ID: 36421731

Budget: £20 – £250 GBP

I have an existing .NET WebService that currently accepts raw Text and works fine.
But I now have to accept raw JSON and it fails. I realise that something in my web.config file needs to be changed and need some help. Attached are all the files and error data.
Related categories: .NET IIS ASP.NET