I'm confused because the SS developers acknowledge that the string can be anything and then mapped within their software.... I have asked that they specifically respond to Ajeh's comments and have yet to receive anything.....
Here's the first reply from the ShipStation developers.....
The strings that is sent to us as the requested shipping service is only a name. In the SS UI that string is mapped to an actual carrier and service combination. You could send me a string that says “paper cup” and match that string to Endicia First Class Mail if you so desired. This has absolutely nothing to do with what we send to Endicia, that is all handled for you automatically by us in the back end.
The problem that we are having is not with the HTML entity ™ or ® but rather that we are getting a double HTML Encoded value in the response from your server. Instead of ™ I am getting ™. As a result this is preventing our system from being able to allow a mapping to be created.
I'm still waiting for their next reply with my knickers unknotted but confused since I don't understand a "double HTML encoded value".