Error in using an External DEM in Snap

Hi everyone!
I just downloaded an external DEM from land.copernicus website in .tiff format at a resolution of 25 m and I would like to use it in the Backgeocoding step, but I am getting always an error saying that “it is unable to download the dem”. I also tried to change the coordinate system but it’s the same.
Does anyone know how to fix this problem?
Thanks a lot,

are you sure you reprojected the DEM correctly to WGS84?

I just tested an area outside the SRTM coverage and used a clipped part of the EU DEM (large red square) and it worked fine:

Or do you mean this error?