Hi @Sathya Chenniappan ,
I see that you asked the same question over on GitHub and a reply has been posted. If you need assistance with your index creation, please reply to the private comment above.
Documentation limit is set to 1000 as we don't recommend a huge number of fields since this would have performance impact with more fields. However, you should be able to continue adding fields to approx. 2000. If you are getting any issue with index creation because going beyond 1000 limit, please raise a support case accordingly through the Azure portal for Search.