Trouble getting patency during endo

Hello!

I'm a new graduate and been struggling with endo. Im not sure why but ive been having difficulty getting patency when doing endo. The canals are wide open on the PA and i use an orfice opener after finding the canals but my number 10 or 8 or 6 wont be patency. Its also at the very beginning so i lieklly didnt ledge the canal. Also the coronol portion is prepared with SX so its not coronal restriction. Im worried its because in vital cases im pushing the nerve tissue down and compacting it with my 10 file. Any tips on how to remove the nerve in one go or remove the pulp tissue without condensing it at the bottom? Is there another reason why I cant get patency in these wide open canals?