Hello Jason,
I had not seen your answer before posting a second time. 
But thank you for your quick response!
at+pn=1 might indeed have been what was causing my problem. I was using at+pn=0, but my packet forwarder configuration file had "lorawan_public": true. I don’t why it didn’t work last night using the Conduit network however, but it is very likely that I was too tired to work on that and I simply missed something(s).
Once again, thank you very much for your time and support. Have a great day. A+
Frank