S3422DWG, DDM no longer working

Hi, I've downloaded the DDM (Dell Display Manager) and drivers for the S3422DWG and it worked for bit. Now it's not working and showing up as an error? The S3422DWG works but the DDM doesn't work. I have attached the error I'm getting below and I've tried everything they recommended e.g display driver and cables. Any help to fix this problem?