My Dry Skin is Back - What's The Deal?

When I first started oil pulling I was amazed at how soft my dry skin was becoming. My cracked heels were almost gone. And now they are back. It's so strange. I thought OP was going to keep me soft forever.

I started with sesame, then went to coconut, then I heard you should periodically switch oils, so I have also been doing castor oil and sunflower oil. I OP once or twice a day for 20 minutes alternating different oils.

And I think I have been Oping about 3-4 weeks now.

I want my soft skin back. What do you think is going on?

Thanks!
Leela