Google tag manager for Shaper helixultimate

Hi,
I developed a website using your Shaper Helixultimate template.
Now, I signed up for the "Google tag manager" service and I have to insert two codes following these instructions:

1. Paste this code as high as possible in the <head> section of the page:
2. You should also paste this code immediately after the opening <body> tag:

I insert the codes from the options template / custom code.
Unfortunately something is not working. The codes can be seen from the front-end. (I attach screens)
Do you have any advice? How can I enter these codes and activate the "google tag manager"?
Thanks so much for the support.
Stefano

https://ibb.co/pXhdH8p
https://ibb.co/27D0c1d