I can't upload my fillable pdf template

When you attempt to upload the .pdf file, does the page show you any warning/error message? If it shows a modal popup similar to the image below, that means you have to upload a PDF file that's actually fillable.

Related guide: How-Can-I-Import-My-Own-PDF-to-JotForm

The import PDF feature only accepts a PDF file that has fillable areas in it.

Otherwise, if it doesn't show you anything, or if it's just stuck, can you share the PDF file you're trying to upload so we can try it from here? You can upload the file through any online cloud storage service (e.g. Google Drive, Dropbox, etc.) then share the download link in your reply.