I just tried this and the labels did not disappear for me, what I suggest is to go back to the Invoice Template in question, change it to a different template (ie Airy) Save it, then go back in and switch back to Modern.

If that doesnt help are you able […]

Resolution for 'apparent reason issue: 'I use the “Modern” Template for invoices, and for no apparent reason the column labels (e.g. “Invoice #”, “Date”) have disappeared. How can I get the labels back?' available: Yes.

The apparent reason issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the apparent reason issue yourself by looking for a resolution described in the article. If it is a complex apparent reason issue or you are unable to solve the issue, you may contact us by clicking here or by using other apparent reason support options.

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