How Do I Fix This?

I don't know what to do after i load the crates he keeps on saying this message.

 

Try going right inside the NPC's hitbox, otherwise switch servers and do it again, though you've most likely done that or walked away by now.

 

Oh my god this bug annoys me, there have been so many posts about it. I spent a while trying to find out the cause, but then someone told me to wait a few days and it will work. I did that and it worked, if that doesn’t work for you then you should look up the other bug reports about this and try their solutions.