It should be "I .wfn" rather than "I.wfn"

Hi all,
For plotting the deformation density map, with manually obtained sphericalized atomic density, I am unable to proceed with plotting the map.

I have added the corresponding wfn file (I.wfn) to the atomwfn folder, and even multiwfn is displaying it in the list while reading the wfn file for calculating the spherical atomic density, but it is unable to read the file.

Can anyone suggest what is the issue here.