Hello,
Can you please check what is the CSS you're using for the HikaShop backend ?
The new checkout workflow is using new CSS rules and if you do have a customized version of it, you could see the editor correctly.
You need to use the "default" one and be sure that it is up to date (and also refresh your browser cache just in case).
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.