Georeferencing a COSMO Skymed raster in QGIS

I’m facing the problem of georeferencing a GEC_B file in both SNAP and QGIS: when I perform few operations for flood mapping on a .h5 GEC COSMO SkyMed file and then write the output geotiff file with
ProductIO.writeProduct(water_mask2, “/home/meb/COSMO/COSMOfinal_mask”, ‘Geotiff’)

what I get is a product georeferenced within SNAP but once exported in QGIS is completly not.

Please note that I followed the step as in

with the exception of reducing the necessary step on COSMO Skymed files to:
as despeckle filtering and terrain correction can’t be applied on these kind of files.

Has anyone ever met a similar problem?