Thank you for playing "Fate/Grand Order".
The following is a message from the administrative team.

[Update - New Information]
We have determined the cause of the display issue occurring within the “Extra Missions” tab and implemented a fix.

Again, we apologize for the inconvenience.
（Added on July 8th）

Within the "Extra Missions" tab implemented after maintenance on 2019-07-07 20:00, missions whose rewards were already claimed may be incorrectly displayed as "Can Be Claimed."
This is a display issue only.
For more information, please see this news post.

We are currently investigating the cause of the display issue.
We apologize for the inconvenience and any confusion the issue may have caused.

▼Date & Time
2019-07-07 21:00 PDT

▼Contents:
1. Within the "Extra Missions" tab, certain missions may be displayed as "Can Be Claimed" even though the rewards have already been distributed.
This is a display issue only. The rewards in question have been distributed as intended, as specified in the related news post:
For Masters who have cleared the following missions before 2019-07-07 20:59 PDT, the story clear rewards will have been distributed at that time.
　* The affected missions are as follows:
　- Complete "Singularity F: Flame Contaminated City Fuyuki"
　- Complete "Singularity F: Flame Contaminated City Fuyuki Section 3, Investigate the Bridge"