My Pinkbar goby and pistol shrimp are having a breakup?

[Gore15]

My pair of snapping shrimp and pinkbar goby somehow are taking a time off. The goby has moved to one side of the tank under a rock a s shrimp has stayed where they lived. 
 

It is now 4 days that they are living apart. I thought the rock cave is small and slightly moved the rocks to make more space in the original spot but the goby is still living in the other rock. 
 

I wonder what has happened that they are living apart and what can I possibly need to do to help them get back together. 

 

 

[Tired]

That can happen sometimes. Leave them alone- they'll either make up or not, and there's not much you can do to encourage it either way. 

[lizzyann]

I tried to get my yasha goby to pair with a pistol shrimp so many times and it just never stuck. They would often live together for a while, then one would end up moving out. I could never figure out if there just wasn't an appropriate tunnel/cave for the two of them or if the goby just didn't really want to be with a shrimp. So yea, it happens 🤷‍♀️. You can try to put them back together but I feel like that often is just too difficult for us or too stressful for them.