I use Mint almost exclusively.  We have one location, however, that I cannot "Reply" to - when I try to reply I get the "Cannot Send: Oops! Something went wrong..." message.  If I switch back to the Classic view I can see the message I typed and can then Reply without error.  As a point of interest, for a period of time I left the support team to work at that specific location and was opening tickets there as a customer.  I have since returned to support -- not sure if that is in any way related to the issue but we are grasping at straws here.  Any suggestions for what we can try would be appreciated.  Thanks.