Hello and welcome to the Community, trhamley
We're not aware of any issues accessing custom form styles in QuickBooks Online at the moment.
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To check for any issues that may be causing this message, please consider clearing the cache and Intuit-specific cookies on your web browser or open QuickBooks in a different browser.
To access custom form styles, click here or select the Cog > Custom form styles in QuickBooks. If you need any further support, please get back in touch below!
