It looks like user id got corrupted when I copied the user to a new user it works fine.
Initially this user was assigned only business role SOLMANPRO and later we added ANALYTICSPRO business role but instead of showing screen for business role selection it just picks SOLMANPRO automatically.
I tried to delete business partner for this user but it says BP is being used in other partner functions. Now how to find where it is getting used ?.. I resolved all open incidents change request wherever the BP for this user used.