Problem with extra’s adding to the total

Hi,

There is a problem when people add extra’s, the total no longer gives an amount but says: +NaN€. What is wrong with it?

Thanks in advance for your answer!

Kind regards, Saskia

• This topic was modified 13 hours, 12 minutes ago by saskia300476.
• This topic was modified 13 hours, 11 minutes ago by saskia300476.
• This topic was modified 13 hours, 3 minutes ago by saskia300476.

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