Landline spam calls

​I am getting spam calls from various numbers on my landline every few minutes.  Many of the numbers are already in my blocked list but the phone continues to ring. Went to nomorobo, did the test call it and it says it's working but nomrobo doesn't show up in my advanced call forwarding. Spam setting is medium since I noted low were some legitimate calls.  I even tried to go back into nomorobo, delete my home phone and start over but that's not an option.  What can be done to stop this?​