If you have a voicemail facility with your telephone provider and an answering machine, when connecting the call blocker, the 2 will counteract one another.
To eliminate this issue, please go into your telephone settings and raise the number of rings your answering machine takes to a minimum of 5/6 rings to enable your answering machine to pick up your voicemail as opposed to your provider.
The Call Blocker uses the 1st ring to determine if the caller is part of blocked caller list so the answering machine is loosing the 1st ring when trying to pick up a call.
By raising the number of rings, this will resolve the issue for you.
If you have any further questions, please feel free to contact us.