As I bought this printer for use by a local organisation to produce a monthly newsletter it was out of use from lockdown in 2020. It had worked well for about 2 years. It is now printing okay but there is a line of dots all the way down the left hand margin. I wondered if this might have something to do with the waste toner box. Although my manual shows how to install it I can't find out how to remove it. Any thoughts on this would be much appreciated.