Connect the authorised playlist
Install Kodi from its official download route. IPTV Simple is the PVR client described in the Kodi wiki for an M3U list and an XMLTV guide. Use the compatible add-on supplied for your Kodi build, enable it and configure the playlist location you have permission to use. If the provider gave you an app-only sign-in, ask whether it offers a separate playlist before entering any account information.
Check channel and guide matching separately
Start by opening one live channel. Then look up a familiar programme in the guide and confirm that the programme matches the same regional channel. If the channel plays but its schedule is blank, compare the playlist’s channel identifier with the matching XMLTV channel ID. Inspect the identifier locally. Keep full files and source addresses private when you ask for help.
Solve a time offset with two channels
Compare two known programmes with the broadcaster schedules at the same local time. If all guide entries are shifted, check the device clock, timezone and the guide offset in the add-on. If only one channel is wrong, ask about the XMLTV mapping for that feed before applying a global correction. Keep a copy of the old configuration so you can reverse the change.