bold black horizontal line across blank document

[Sheebacat]

I have a new computer with Microsoft Office.  I do not understand why, when I pull up "blank document", there is a bold black line across the top of page.  When I start typing, it types in the black bold line.  I cannot even see what I'm typing.  How do I get rid of this please?

[#2]

@Sheebacat Can you upload a copy of a document so that we can investigate the issue.

[#3]

tell me how please

[#4]

@Sheebacat When you click on Reply, you will see the facility hight lighted in yellow by which you can Drag and drop here or browse files to attach.