how to change the amount of a customers recurring monthly invoice ?

You can edit a recurring invoice amount from your customer in the Category details using your QuickBooks Online (QBO) account, Mike. Let's work on this together, one step at a time.

Firstly, you can hover over the Gear icon and select Recurring transactions. By doing this, you can be routed to change its amount for your customer.

Moreover, it's essential to know that editing a recurring template can be tricky as these changes can affect items, customers, and company settings.

However, recurring templates can help you save time. You can make recurring templates to automatically create invoices, expenses, and other tasks you do regularly.

To edit a recurring invoice, here's how:

1. On the upper right corner, look for the Gear icon.
   
2. Select Recurring transactions.
   
3. From the Action column, click Edit for the transaction you want to edit.
   
4. If you're editing a Scheduled or Reminder-type template, you can adjust how far in advance QuickBooks creates the template or sends you a reminder. You can also set the frequency in the Interval section.
   
5. In the Category details, change its amount for your customer.
   
6. Once everything's okay, select Save template.

For more information, I've added this article: Edit a recurring template in QuickBooks Online.

Additionally, here's an article you can browse just in case you want to modify, suspend, and track your existing recurring payments: Modify existing recurring payments.

Lastly, to enhance the efficiency of your accounting practices and ensure impeccable financial records, I highly recommend considering QuickBooks Live Bookkeeping. This provides direct support tailored to the strategic areas that drive business growth and success.

I'm glad I assisted you with adjusting your invoices in QuickBooks. If you have any more questions or need additional help, please feel free to reach out at any time. Wishing you continued success in your business endeavors, Mike.