No. There is no limit to how many times you can take the test. Likewise, colleges do not care how many times you take the test. Most colleges will only look at your highest ACT score or use a mixture of your highest sub-scores from all your tests.
Same thing for a scholarship. You would report your highest ACT score (or sub-scores) for the scholarship, and then verify that you're reporting the facts by sending in your scores to the scholarship committee. For the ACT, you can only report one test date's score, through the online method, at a time. So you have complete control of what they see.
Good luck!
