This is hopefully working in the meantime. I'm closing this as the test data is incomplete and thus the bug can't be reproduced. Please reopen if the problem still persists.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
also the buffer size that i am using is constant 0.2
Sorry. I attached the wrong file. This is the shape file. it is larger than the first one. 7 MB
This is hopefully working in the meantime. I'm closing this as the test data is incomplete and thus the bug can't be reproduced. Please reopen if the problem still persists.