HTML Tags in Product Description

Hi all,

So as my listing was changed a few weeks back as someone else decided to list on it, my product description had all bunched up and basically looked horrendous compared to what I had it as originally.

When I go to report it the product listing, the page says that I cannot use HTML tags which I find absurd. I have opened a case with seller support regarding this but am not too optimistic about receiving their help.

Can anyone who has experienced this please advise me?

Thank you