Why is my iCloud backing up to a device that has been deleted?

I had an eight-year-old iPad that my daughter used linked to my AppleID. I have since deleted the device in iCloud settings and it is also gone from Apple ID on my iPhone. I am trying to back up my iPhone, which is the main device on my account but it continues to back up the iPad even though it does not show on my Apple ID account any longer. I updated to the latest iOS on my iPhone and tried again. The time and date of my last backup shows accurately but when I log into iCloud online to manage my photos, etc., it is still pulling what was on that old iPad. The iPhone is the only device showing on my iCloud. Any ideas how I can get it to recognize my iPhone data?