I have this problem that sending an email never finishes. I have this group of contacts that has around 200+ members and it seems that the action "Send an email" in the office 365 workflow won't send the email or get stuck in sending the email. But when I just put my email in it, the workflow successfully run. But when I created this kind of workflow in the On-Prem version it does successfully run without errors or even being stuck.
Also, some of the members of the group already left our company so some of the email in the group does not exist. But still I don't get the email saying that "Delivery fail" or any other error stating that it fails to send a particular email on this person that doesn't exist.
Is there anyone here experience the same thing as me? If yes, how did you resolve this issue?