Special character ‘ blocks TAX from being calculated

Hi, a customer of mine is using Flexible Shipping for Woocommerce. It works great. Except for one thing: when a customer uses this sign: ‘ in the city field, the Tax is not being calculated. So I am talking about that high comma (‘).

Can you like add that sign: ‘ <- copy it – so it does calculate the Tax?

Thanks in advance!

Regards,

Peter

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