Only meta tag was added to the same page, but the crawler doesn't work

I wanted to add an OG tag from the current page, so I made a new page with the same content(plus og tag) and made a new link and tested it, but when I clicked the "See exactly what our scraper sees for your URL(https://developers.facebook.com/tools/debug/)" button, a white page appeared and I saw the code before adding the OG tag.
Of course the OG tag was not recognized.

example
original api : www.test.com/hello/{code} move current page
new api : www.test.com/hello/test/{code} move new page(plus og tag)

using spring boot + handlebars