Answer:
A phone call
Step-by-step explanation:
In this case where the supply chain specialist who has the information is not online, the best way to contact him is via telephone call.
It is so, because it's very easy to reach out to people via telephone call.
One advantage of the telephone calls is that, calls can be made at anytime 24 hours a day, 7 days a week
Lastly, fhe telephone call, which serves as a connection between a caller with via human voice, creates a connection that's not present in other media.