There are several factors that may cause a check to be rejected. If a check is rejected, you will receive an email notification followed up by a chat in your online banking with exact reasons as to why.
If a check is rejected and you are instructed to try and redeposit the check, you might get a message saying that check has already been submitted for deposit. That happens because your phone stores that check information. If that happens you can make the deposit the next day (via mobile deposit), or at an ATM or branch the same day.