Two page numbers can appear on the same page when you have section breaks but do not turn off the "Same as previous" footer. The following site refers to earlier versions of Word but the concept is the same. Ensure that you are not accidentally linked to the previous section's page numbering by checking the "Link to Previous" option in the "Page Number" settings.If you want different page numbering styles in different sections of your document, unlink the sections by going to "Insert > Page Number > Format Page Numbers" and deselecting the "Link to Previous" option.