Bnet Whisper not working - error 7004

Whenever I try to message someone in a new chat on the desktop app’s social tab it says “! There was an error delivering your message to [name]. (7004)” I do not, however, get this error message when messaging friends I already had in friend’s list for a while.
It seems like the error only occurs for newly added friends (that I try to trade with in D2R) would cause this error. Anyone else having this issue?