Let's run some troubleshooting steps to resolve this issue, s-hawk1256-sh.
Let's ensure that you've selected the is CIS contractor option within your customer details section. This would populate a field on the invoice for the CIS deduction and have you enable the CIS.
If the same thing happens, let's try turning the codes off to go out of the page and then go back in and turn them on again. Then, go into the invoice and see if the codes shows up.
If the issue persists, let's open QuickBooks on a private window. It is the best place to identify for any browser related issues. I've added these keyboard keys to open one:
Google Chrome: Ctrl + Shift + N
Mozilla Firefox: Ctrl + Shift + P
Microsoft Edge: Ctrl + Shift + P
Safari: Command + Shift + N
If you're able to find the reverse charge option, we can go back to a regular browser and clear its cache. A piled cache can also be the reason for some unexpected issues on the opened pages.
We can also switch to a different supported-browser like Google Chrome, Mozilla Firefox, Safari, or Microsoft Edge.