Please match the format requested – space character bug

Hi,
A client has been complaining about an error on their website for a few months, but I’ve been unable to replicate it myself, until now.
When the end-user fills in product fields such as ‘First name’, ‘Surname’ etc before adding a product to their basket, they were seeing the error ‘Please match the format requested’

This has caused my client to lose many sales, as their customers became frustrated.

Yesterday I found out what was causing the error. If you fill in the field but put a space on the end e.g. ‘Sarah ‘, the field gives the ‘Please match the format requested error’.
The same also happens if the field contains non-alphabetical charecters such as apostrophes or hypens. UK names often have an apostrophe or a hyphen e.g. “o’hara” or “smith-johnson”.

This is a serious issue which is affecting my client’s sales. Please can you suggest a fix?

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