Breech position at 30 weeks

Second time mom here and my we had our CAS last month, my baby was in cephalic position. Now at 30 weeks we had our 4d ultrasound and the OBSono said she is now in breech position. Any reason why my baby moved to breech? Were you able to have normal delivery even though baby was on breech position? Also please include us in you prayers because when we had our CAS, there is a thickened nuchal fold seen on my baby. Thank you very much. #breech #30weeks #pregnant