I want to extend my tiebacks on curtains so curtain can hang looser

what are the existing tiebacks made of?

If you have plenty of the fabric to work with, move what you anchor the tieback closest to the window further out, that may give you a looser hang.

Try sewing and extension to the tie back in the same color as the drapes. Good Luck!

I recommend adding rings at both ends of your current tie back. You can add as many rings that you think work. You sew them on or glue them on. That will give you longer length of your existing tie backs. I hope this helps you. Good luck.

For something a little different, try finding some cheap jewelry necklaces with large rings, take them apart and add some of the necklace to your existing tie backs.

You could swap out the tiebacks with ribbon, I agree with Janet, what are the tie backs made of, that would be the question to start with.