False recorgnition

[rugema3]

Dear Community,
I have been using compreface for quite some time. I installed it on a separate server, and have been accessing it fine.
I am using recognition to integrate with my attendance table. I am able to add subject in the face collection so that they can be recognized later.

so far we have 47 faces with 78 images.
recently, the recognition is off big time. every time the employee looks in the camera, it recognizes someone else. The similarity is above 90%.

I am having a frustration. Did anyone ever face an issue with recognition with face collection? If you did, did how you handle the issue? Please help me out.