I haven't serviced a Rowe validator in years. So many changes to our money have occurred. I could probably help with an amplifier, but not your currency validators.
Your unit may need an upgrade, or it may be old enough it cannot support the newest bills. Or it might have a problem that can be adjusted. If it were mine, I'd contact Rowe and ask about it.
Education is what you're left with after you have forgotten what you have learned.
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