Presumably it throws an exception and posting that exception as part of your post is helpful.
Presuming that the exception is telling you the statement is too big...
If your SQL statement is too long then SQL/C# will have a problem with it. The solution is to reduce the size. (Might note that that could indicate a database design issue as well.)
Using the database import tools (sqlldr?) might help with the problem but might not. If not or you don't want to use it then solutions.
1. Do two calls.
2. Pass in a blob and parse it to create dynamic sql.
If it was me I would presume that there is a design issue.