When editing the emails, again and again after writing the correct url for envelope.png - the src urls are automatically modified

<img src="https://mywebsite.com/https://mywebsite.com/https://mywebsite.com/https://mywebsite.com//components/com_adagency/images/envelope.png" alt="ij" width="15px" height="auto" />
It seems - I checked and Yes I can confirm - each time I modify the url in an email template it ads the src url in all other emails
I would like to add that I edit with "no editor" to avoid any conflict...
I am not allowed to give back-end access can you please check on your side?