Group Texting only supports sending plain text, as certain characters are rendered differently on different mobile telephones. Any character copied from an outside source can appear incorrectly. If you are copying and pasting from an outside source (such as a Word file), retype it manually, because there can be hidden characters. You can test this by sending the message to your own phone.
Also, handsets render characters differently, so you can try changing your phone settings.
We allow the following characters: a-z, A-Z, 0-9 and these special characters: .,:;!?()~=+-_\/@$#&%
Important: Group Texting does not guarantee delivery or timely delivery. Group texting is an online application that enables users to store contacts, organize contacts in groups, send and receive SMS, and use keywords on our long codes. However, we do not deliver your messages to the handsets. We only deliver your messages to the wireless carriers. You are paying us for the use of our application and sending messages through our gateway to the carriers’ gateways. You are not paying us for the delivery of messages, because we do not own nor operate the carriers’ gateways.