I understand how important it is to quickly access these documents, especially when you're on the go, @waveneyvalleyfire. I recommend uninstalling and reinstalling the app that receives the invoices, such as Gmail. This process will refresh the app's settings and ensure it's compatible with the latest updates.
On the other hand, restarting your device can also help. This action clears the cache and refreshes the system’s resources, which can eliminate temporary issues affecting your app's performance and file downloads.
In addition to these steps, consider accessing the app via web and mobile web browsers. This way, you can view and download the certificates attached to your invoice and efficiently continue managing your invoices.
Before we proceed, I'd like to clarify your inquiry regarding reverting to a prior version of QuickBooks Online (QBO). If you meant to switch back to a previous subscription, then yes, we can downgrade your current plan. Please let us know your preferred plan, and I'll gladly assist you in making these changes.
- Sign in to QuickBooks as a primary or company admin.
- Go to Settings, then Subscriptions and billing.
- In the QuickBooks section, then Downgrade your plan.

- Review the available plans and click the Choose plan button.
- Follow the onscreen steps to downgrade your plan.
However, if your question pertains to switching back to an older update, please know that QBO operates on a cloud-based system, and updates are continuously rolled out to improve features and security. Once an update is implemented, reverting to a prior version is not supported.
Once your customers pay their invoices, let's record the payment using the Receive payment feature in QuickBooks to mark them as paid.
You can also generate the Open Invoices report to track unpaid invoices and statement charges, with totals for each customer. This way, you can effectively manage your accounts receivable.
Have you been able to view and download the certificates after trying these steps? If not, please let me know by clicking the Reply button. I'm here to assist you with any further support you may need.