First bub was head down at my 20 week scan and stayed that way.

Second bub was all over the place, he was always breech or transverse until he finally turned head down at 32 weeks and he stayed down then.

Don't stress yet your bub still has plenty of time and it's not uncommon for second/third etc babies to move into position much later - your uterus has alot more "give" having had a baby before so they can easily move around for longer. While ever baby still has a fair bit of room they are going to continue flipping no matter what you do. If still not head down at 32-34 weeks that's when I'd start trying to turn her.