clean laser lense with a cleaning disk and if no luck clean with a cotton bud dampened with a little water. If still a problem take a note of the laser KSS number and obtain a replacement from:
www.cpc.co.uk or www.charleshyde.co.uk
But if more than one laser shown check the ribbon cable socket is the same and when it arrives remove the static electricity protected soldered shorting link before installing.
No adjustments are required.