the "Your first application" example code does not run, gst_pad_link() return GST_PAD_LINK_NOFORMAT

Hi, I'm studying GStreamer by reading the official tutorial, the example code in "Your first application" can be compiled on my machine,but it does not run,I found the call to gst_pad_link() in on_pad_added() encounter error,the return value of gst_pad_link() is GST_PAD_LINK_NOFORMAT, what's the meaning of the error? How to fix the problem? My platform is Windows 10, I compile the example code using VC2019;