The Invoice page will disappear automatically after you've clicked the Save and close button. The transaction will be saved in the Sales menu.
However, if you're referring to clicking only the Save button not Save and close, you may need to perform the browser troubleshooting method. This is done to check if this is a browser-related issue.
First, you have to use an incognito browser to see if you need to clear your browser's cache. If you're able to click the Save button without having the invoice page disappear, you may go back to the regular browser and clear the cache. An alternative way is to use another supported browser.