What can be said when I need to dismiss an expectation?

Here are some examples of what I mean by "expectation":

* I ask someone what time it is, then I remembered that I'm actually wearing a watch. The person expects to tell me what time it is but I no longer require help. (Expectation created by me)
* I suspect I do not have enough coins to buy a drink from a coin-only vending machine. I ask someone for change. However I discover that I indeed have enough coins with me. The person still carries an expectation to help me although I no longer require help. (Expectation created by me)
* A waiter offers to refill a glass. He is expected to serve me because of the nature of the job. I do not wish to have a refill. (Expectation not created by me)

I came up with `もう要らない` but I think saying that is unnecessarily direct in conveying "I no longer need (help)".