Convert JSON object to String and vice versa?

I am making a new WYSIWYG plugin, my plugin data is coming out in JSON format, but I need to store it in String. I use JSON.stringify, after saving the response in the API, I see the data in this form "{\" time \ ": 1628685159691, \" blocks \ ": [{\" id \ ": \" Mp4T9uh217 \ ", \" type \ ": \" paragraph \ ", \" data \ ": {\" text \ ": \" kdf \ "}}, {\" id \ ": \" qed1fKEoNo \ ", \" type \ ": \ "paragraph \", \ "data \": {\ "text \": \ "asdf \"}}], \ "version \": \ "2.22.2 \"} ". When I get it back into the plugin, I am unable to embed the previously saved data back. I do not understand what could be the problem, does anyone know how to solve this problem?