A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
The formula looks OK - assuming that you use US date format MDY. Are you absolutely sure that there are rows that match all four conditions?
If possible, could you create a stripped-down copy of the workbook demonstrating the problem (without sensitive information) and make it available through one of the websites that let you upload and share a file, such as OneDrive, Google Drive, FileDropper or DropBox. Then post a link to the uploaded and shared file here.