Hi, Unfortunately, this is caused by the printer head. It will gradually stop working. However, some things to try is to clean the print head. This is literally opening the printer and cleaning the head. Also, avoid using refill ink cartridges as they damage the print head a lot quicker. Get brand new cartridge if you are using refills. If this still doesn't help, then the print head have already been damaged and need to be replaced. By the way, if this printer is still under warranty, brother should replace either the printer or the print head for you free of cost.
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