I had very similar problem with an application from my vendor, so I couldn't reach the code

The solution for me was accessing the nuget.info site and download the Oracle.ManagedDataAccess.dll manually and replacing it in the app folder

I picked the latest release for the 2.19 on the site, which shows as 2.19.250 https://nuget.info/packages/Oracle.ManagedDataAccess.Core/2.19.250 lib-> netstandard2.0-> Oracle.ManagedDataAccess.dll-> double click on it and the browser downloads the file

The product version shown on Windows Explorer is 2.19.1:20240910 against the 2.19.1:20200326 that came with the vendor app