The sutra on the Mahima Form has to be changed only if it breaks, gets damaged or burnt. A new sutra can be purchased from Isha Life. Please click here (https://ishalife.sadhguru.org/in/bond-of-grace-sutra) for the Isha Life link.
The old sutra can be removed by untying or burning it. Do not cut it. Dispose of it by burying it under a tree. The soil should be kept wet for a few days. It can also be put in flowing water, such as a river, or a large water body, such as a lake or ocean. It may also be disposed of by tying it to a flowering tree.
Please click on the link below
(https://drive.google.com/file/d/1Nvek52gp66HfIn0G8EZkOnQ8aVAJJobb/view?usp=sharing) to see a video on how to tie the Mahima Form sutra.