How to fix Bitmap failed to stabilize error on Silk Test

getting below exception on captureBitmap() method for desktop application

Silk Test Workbench

Playback error in the .NET Script 'TestSuiteDriver':

SilkTest.Ntf.BitmapNotStableException:
Bitmap failed to stabilize. 

i have added the below code in vb.net script. 

Agent.SetOption(Options.BitmapMatchCount, 0)
Agent.SetOption(Options.BitmapMatchInterval,0)
Agent.SetOption(Options.BitmapMatchTimeout,0)

but still getting exception. 

need to configure something in silk test workbench?  please help...