Failed to download dependencies

Project
  org.onap.so:common:jar:1.6.0-SNAPSHOT could not be built, as one of 
its dependency chain, 
org.onap.appc.client:client-lib:jar:1.7.1-SNAPSHOT: Failed to read 
artifact descriptor for 
org.onap.appc.client:client-lib:jar:1.7.1-SNAPSHOT failed to resolve, 
because we could not download artifact { 
org.onap.so:common:jar:1.6.0-SNAPSHOT,3} from repository { 
org.onap.so:common:jar:1.6.0-SNAPSHOT,4}.
Reported cause was: 1.7.1-SNAPSHOT..
Indication 1