Deep breath, then take one thing at a time, try
1. Power on TV first then Humax if no success try
2. Humax first the TV, if no success try
3. Scart connection to try and get everything back to a working config then
4, Reconnect HDMI and cycle through resolutions using the vformat button see if you can find one that works.
5, Check Samsung website see if there is an update for your model of TV?