Troubles with RINEX coordinates processing

Hi,
I'm trying to build a 3D map, similar to http://stuffin.space but with calculated satellites positions from RINEX navigation data.
I'm processing RINEX 3.03 navigation data, calculating XYZ (ECEF). I'm then converting those ECEF coordinates to WGS-84 :
ecef = pyproj.Proj(proj='geocent', ellps='WGS84', datum='WGS84')
lla = pyproj.Proj(proj='latlong', ellps='WGS84', datum='WGS84')
lon, lat, alt = pyproj.transform(ecef, lla, x, y, z, radians=False)
I'm then adding those points to a JSON, and I use https://www.alexras.info/code/orbital_objects/ to put them on a 3d map.

Here is what I'm getting for a single satellite, based on all the time predictions from the RINEX file :

Why am I not getting a nice orbit (like this one) :


I don't get what I am doing wrong

Thanks a lot, and sorry if this has already been answered

 

What is the plot in ECEF coordinates?