When a child shares a feeling, what they usually need is not an immediate solution, it is seeing that what they feel is accepted, even when it does not seem logical to us.
Phrases like that is nothing to be upset about or there is no reason to cry might stop the tears in the moment, but they also teach the child that their feelings are not welcome.
Instead, try saying I can see you are really upset right now. This simple sentence tells the child their feeling is real and accepted, even if the reason behind it seems small to an adult.
A child who grows up feeling heard learns, over time, to express their feelings instead of hiding them.