WHM won't let me use @ when trying to specify my SPF record. It was mysite.com., where there is a period at the end.

I tried @, but then get this error message: "Unable to parse zone: Contains a malformed DNS label: @"

I tried blank, but that just copied the text from the previous line, which was ftp.

So, currently I cannot set up my SPF record. 

Anyone else with this issue or a solution?