Problem with Exporting from Access to excel .xlsx file type

I have a form in Access that contains a column of suppliers among other items.  When I export to .xls all is fine and appears as it does in Access.   But when I export to .xlsx file one of the supplier names gets concatenated with another spelling of the same name.  Almost like its auto filling in the name.   Example -  a supplier is CompanyX in Access and .xls files.  But in the .xlsx file it comes out as CompanyXCompanyyX   This also happens if I do a straight cut and paste into excel.

Any ideas are very much welcome.