Technophobe

hello we just bought the LG OLED 65C1 tv. on our previous Samsung tv we were able to use a Samsung sound bar connected via hdmi and wireless headphones (that uses a the charging base plugs into the audio port on the tv and then red and white leads that plug into the charging base ) for some reason we can't get the sound bar and headphones to work at the same time any more? we have tried plugging sound bar into optical port rather than hdmi and the headphones into audio port but still we can't get them to work at the same time. what do I need to do to get both sound bar and headphones to work at the same time?? thanks