can not change the name on the header for my marketing materials
HI, hopefully this Square Support page will help.
https://squareup.com/help/us/en/article/6194-customize-marketing-campaigns
Please note, if you changed business name after signup, and changed everywhere within YOUR dashboard, the original business name is still active on Square's backend dashboard.
You can try to contact Customer Support with this link. Monday to Friday, 6:00am-6:00pm PST. (Thursday & Friday are Holidays)
Contact Customer Support
https://squareup.com/help/us/en/contact?panel=FAB456B04971&skip_unit_select=true
You will get a few options to contact, click Call Us, a new browser window will open with phone number and customer code.
You must be logged into your account and is best on a laptop or desktop. Phone app sometimes displays unavailable at times.
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