This is a developers forums and all issues related to users account will not be answered.
See https://support.twitter.com/articles/66885-why-can-t-i-follow-people for the Help Center article on following users.
From @Radio_Silence1:
Hello, I don’t use Twitter much but the other day I logged in and started following people (that were following me)back. I was suddenly suspended. Is there a limit regarding the amount of people I can follow back?
