Problem with debugging

I was following a course on how to use GTM, after installing the plugin and entering the ID code, I went to debug but Tag manager can’t connect to the site. I contacted google and they tell me that the problem is due to the plugin and they suggested that I contact the assistance in question.

This is the message from GTM:

There are currently no debuggable Google tags at that address. Please verify that:

• There is a Google tag on the page.
• The Google tag is not a legacy tag. Learn more
• The Google tag is not being blocked, e.g. by a browser extension or a consent dialog.