Hi CaesarRodney,
Thanks for coming to Apple Support Communities for help today.
Is your iPhone fully updated? You will want to make sure it is and the issue isn't related to an outdated version of iOS. Here's how to Update your iPhone or iPad.
Are you syncing your Calendar with iCloud or any third-party services? Have you checked elsewhere to see if the result is the same?
If this is a third-party service you sync with, go to Settings > Calendar > Accounts and remove the account and add it back. If the issue remains, you'd want to contact their support.
If you are syncing with iCloud, check the iCloud website through a computer's browser. Does the discrepancy show up there? If it does, contact Apple Support for a deeper dive.
Have a fantastic day!