@rhiannonfayblay this is commonly a T-con board error (Gamma Chip). Since your TV is a bit off-brand we would need to see what it displays. Post some pictures of what this all looks like. After that, unplug it and remove the back cover. Then take a look at the boards. Check for loose cables as well as corrosion on the cable connectors. Look for obviously damaged components. Post some pictures of all of your boards etc. with your Question. That way we can see what you see.
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