On Wednesday, Twitter users were faced with the errant warning: "You are over the daily limit for sending tweets."
And the team responsible for the service had all left the company in November, per Platformer.
In a private message seen by Insider's Kali Hays, one Twitter employee described it as "a massive outage."
Since Musk took over the company, employee numbers have fallen more than two-thirds, from over 7,000 to around 2,300, per the billionaire himself.
After Wednesday's outage, Musk emailed Twitter staff telling them to "pause new feature development" in order to ensure "system stability and robustness," Fortune first reported.