Epson LQ 680 ejects paper very often

[i-have-fax-problems]

Hello,
I have a customer (doctor) who prints the DinA6 prescriptions with the LQ 680.
Very often (not every time) the printer feeds the papersheet from the front but ejects it again.
When you insert it a second time the printer prints it just fine.
What can I do?

Thank you.

[GIUBOSS]

Hello,
I have a customer (doctor) who prints the DinA6 prescriptions with the LQ 680.
Very often (not every time) the printer feeds the papersheet from the front but ejects it again.
When you insert it a second time the printer prints it just fine.
What can I do?

Thank you.

First of all I would do a complete maintenance, blow on the paper sensors, rub the surface of the rubber rollers with a cotton rag moistened with degreaser.