Copy and Paste breaks hidden text

I designed some years ago a routine to create a ‘Quote’ from an ‘Enquiry’ form which is then faxed to a customer - which has suddenly broken!

Typically users will copy and paste info into the originating Enquiry field from their email as part of another process and then when ready to quote (fyi the reason the field is there is it saves the users time switching between forms)

The Quote form displays a field from the Enquiry form which is hidden when printing (ie faxing to the customer) as this field contains sensitive information

If text is entered into the originating field the hide works

If text is pasted into the originating field it displays

I have tried:-

@GetDocField

Computed Text

Making both fields Text and/or RTF

I have tried writing QueryClose and QuerySends to clear the field - these do not work after a paste

Copying from a doc in read and in edit

Any suggestions?