I sent a Settler from Starlight to Graygarden and told them to set up a supply route from there back to Starlight

I went to Graygarden and had to create a bed for them, the route showed up on the map and the Brahmin appeared but the Provisioner never showed up

After a while the Supply Route seemed to disappear from the map

So I sent a Settler from Hangman's to Graygarden and again told them to set up a supply route from there to Starlight.

The route Appears on the map, I go there to build a bed for them, the first one still shows as assigned so I have to build a second one. The Brahmin is still there as well

After a while the Supply Route seemed to disappear from the map again

So this time I send another Settler from Hangman's but don't tell him to set up a trade route this time.

He gets there safely, I have to build a bed for him as the first two are still showing as assigned, and the Brahmin is still there. I check the map and the Supply route appears to be back so I have him pick Mutfruit

I tried walking between Graygarden and Starlight to see if I could see the stray Settlers/Provisioners but no luck

They still show up in the population count for Gray Garden and still have assigned beds and the supply route seems to be working (for now) just no sign of them.