This page of the Biomutant guide contains a walkthrough of the Find the Ring-dinger side quest. We have described everything you need to do in order to complete the quest and earn the rewards.
Starting the quest
How to start: Talk to a man in town - Namby.
Reward: 200 XP.
To start the quest, you need to talk to the man by the wood. He mentions the phones, scattered across the map.