Hi there, Thanks for reaching out. This is listed on our [url=https://help.bungie.net/hc/en-us/articles/39007140765204-Destiny-2-Year-8-Known-Issues-and-Vital-Information]Known Issues[/url] page: [quote]Mythic Campaign missions are sometimes not granting players Triumph progress when other members of the fireteam are at different campaign completion states. Players should ensure that they have unlocked the mission they are attempting to complete at higher world tiers in their own playthroughs prior to running them.[/quote] Please rest assured the team is aware of the issue and looking into it, and we apologize for the inconvenience in the meantime. That said, the workaround provided above should help.