This previous-school trick will liberate the toner particles which have been trapped to the inside walls and nooks. Once you mount it back again towards your printer, it may well register it as whole. You might require to deactivate the ink-preserving manner for your printer to detect toner levels properly. https://hp-printer-ink-6170246.ageeksblog.com/36497586/examine-this-report-on-printer-hp-ink-tank-315