Best Thread To Attach Fall To Saree

I practiced blind stitch on the hem of pants but it PUCKERED!

I don't want saree to PUCKER.

Then I realized that I used nylon embriodery thread to do blind stitch on pants.

My Question: What thread to use to attach fall.

Google search says

1. Same color thread
2. "Invisible thread"

When I search "Invisible thread" on Amazon I get results for Nylon thread.

https://www.amazon.com/s?k=invisible+thread&ref=nb_sb_noss

But I thought Nylon thread is no good


This one has size of thread, .004 it seems
https://www.amazon.com/YLI-Corporation-Wonder-Invisible-Thread/dp/B00A2GSI3I/


This thread says it is used for arts and crafts, nothing about blind stitch!
https://www.amazon.com/SINGER-260-Invisible-Thread-135-Yard/dp/B000IGEBSS/



Soon lockdown will be over and we'll be going out. I wish to attach fall to saree without PUCKERING.


Please help!