Hi and welcome to the forum
What are the tank dimensions (length x width x height)?
Can you post a 1 minute video of the fish?
You can upload videos to YouTube, then copy & paste the link here.
If you use a mobile phone to film the fish, hold the phone horizontally so the footage fills the entire screen.
Can you also post a picture of the fish and one of the entire tank?
What are the ammonia, nitrite, nitrate and pH levels in numbers?
What sort of filter is on the tank?
How often and how do you clean the filter?
How often do you do water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?
Do you dechlorinate the new water before adding it to the tank?
Did you add anything new to the tank in the 2 weeks before this started?
Did you do anything to the tank on the day before this started?
What do you feed the fish?
What does the fish's poop look like?
Does the fish look fatter than normal?
Is the fish sitting on the substrate or in the water column a bit above the substrate?
Assuming the fish isn't sick and the water is good, some fish do sulk if their owners go away. Cichlids in particular can sulk if something changes in their life. It can be the addition of new fish, rearranging the tank or adding/ removing items from the tank. The fish might be upset because you aren't there all the time now. However, we need to check it for diseases and we need to know the water quality.
Second issue is the number of tiger barbs. All barbs do best in groups of 10 or more and they stress when kept in small numbers. However, your tank might not be big enough for that many. Do the 2 tiger barbs get along or do they fight?