[Q] cant restore nandroid backup topic

so i decided to test out Dynamic Kat 4.0, i was using 3.0 just fine but i wanted to try it. i backed everything up in twrp recovery flashed 4.0 and every was fine i decided to go back to my old rom (3.0) simply because the different isn't really noticeable and i cant bother to set my phone up again, restored the nandroid and my phone gets stuck in bootloops, wont boot at all, is there something i am doing wrong i ticked everything in backing up and restoring.