Hello @user5470 ,
The reporting issue only seems to be affecting your regular newsletters, not the custom code ones. I had a higher level technical agent take a look with me, and we're not noticing anything internally that would be causing the emails to not actually be sent, or that would be causing any glitches in reporting.
At this point, I'd recommend you reach out to our Deliverability team, and specifically make note of what emails have been affected or not. Additionally, you can reference this case number (26488933), that way the Delivery agent will immediately have notes to look through.
I do apologize for the inconvenience, in order to find a solution for you and to do some troubleshooting on this, we will need you to reach out to the Delivery Support team. I also recommend checking with your IT department to see if your email went to spam. You may benefit from self-authentication which our Delivery Support team can assist you with. Thanks.