Debug a val dataloader in ML project

I want to load two input imgs and one gt img at the same time, like 0024.flo (gt) and 0024_img1 and 0024_img2 (inputs). Current train loader works great, but the val loader appears 0036.flo (gt) and 0030_img1 and 0037_img2 (inputs), which is not as expected.