Jessy_Nick,
I was able to figure out my issue. Check the tweet length on the history of the failed run. Copy/paste what would’ve been the tweet into a potential manual post to see if it exceeds the length…mine did even though it’s specifically not to exceed. 403 is also the error that twitter returns for those users exceeding the 280 character length that “could” exceed if they are verified. The error is technically correct “we are not permitted to perform this action” UNLESS we were verified. Hope your issue was the same as mine and this is what it is.