Do you have the problem in other games? Such as a test game? Are you using an unsupported browser, or an extension such as Beyond20 to funnel in rolls from DnDBeyond? This could also be due to a corrupted Chat Archive. A game's Creator is often able to fix issues with their Text Chat by clearing the Chat Archive (note: not clearing your current Chat Log ). A GM might want to copy/back up the Chat Archive before the Creator clears it.
