My chins suddenly became really fearful

So I’ve had my chins(1 male 1 female) for more than a year now. They love to get handled in the past and would run and climb around me during playtime. However, recently they suddenly got scared and would bolt away the moment i open the cage. Also, when i do catch them to put them back into their cage after playtime they drop a ton of fur. I’ve now kept them in the cage without playtime for 2 days but whenever i do come to the cage to check them out and greet them they would run into their hideouts. I’m scared as i don’t know what happened to the two of them. What should i do to help them calm down or rebuild our bond we had in the past?

Note: i do not have any other pets