GrapesJS - can't edit

My Mautic version is: 4.2.0
My PHP version is: 7,4
My Database type and version is: Mariadb 10.3.34

My problem is: I can’t add new blocks to any templates while editing in GrapesJS. I’m not up for programming right now, and miss the ease of the old template editor (I had to build a new system after the old server died on me - no big loss of data)