Hi @bbseejh,
Thanks for reaching out with your question!
Daily and hourly impression caps limit the number of ads that can be shown to a particular user. For example, if you only want a user to see one ad a day from a particular network, set it to one daily impression. These caps do not limit the total number of ads that can be shown from a network.
If you are looking to limit the number of total impressions served by a network in a given day, your best bet is to create a budgeted network line item.
If you still have questions, please reach out to the MoPub Support Team at support@mopub.com with a summary of your question, the email address associated with your account and the related ad unit ID.
Thanks!