Programme listings and video streams are separate. An empty guide can be a source or matching problem even when the channel plays normally.
Check the guide source
Ask support which programme-guide source belongs to the playlist. Some players receive it with the account; others need a separate address. Avoid replacing your account simply because listings are missing.
Check channel matching and time
Refresh the guide and allow it to finish. Check the device time zone and any guide offset. If only a few channels are empty, tell support which ones: guide identifiers may not match those channels.
Collect a useful example
Record the channel, expected programme, displayed time and whether playback works. Hide account tokens in screenshots. An exact example is more helpful than a general report that everything is broken.