I have a scenario and in that I want to append a closing tag then some other tag after that opening Tag of the first closed Tag. For Example: I have this code <ins>123678</ins> and I want to append <b>46</b> in between 3 and 6. I tried this code while putting my cursor in between 3 and 6

document.execCommand('insertHTML',false,'</ins><b>45</b><ins>');

But it is not giving me desired output. I want my output like this

<ins>123</ins><b>45</b><ins>678</ins>