EPG: tvg-id tags M3U matching with XML, but EPG empty?

Hello

I’m new here and I don’t know Kodi very well. I use Kodi Krypton 17.3 on my NVidia Shild Box (Android 7) with the PVR Simple IPTV Client.

The issue:

What ever I do (and I’ve checked and double-checked this many times), the EPG table is always completely empty as well as not any channel information to each channel. I’ve really compared the tvg-id tag in the M3U file many times with the (remote loaded) EPG XML file – and they are identical! I’m absolutely frustrated because I don’t know what I still should check. I think it should work, but it does not.

I can provide my M3U file, my XML EPG file, my Kodi log file – what ever you want.

Important to know: The same M3U and XML file works perfect together for EPG when I use it for example on my Android smart phone with an IPTV app like GSE Smart IPTV from Google Playstore(!)

I would be so grateful for any help on this.
Sorry for my bad english, it’s not my native language.

Kind regards
Roman