No Bug Here
You can't upgrade Basim to 3 Star DNA yet for completing Mission 22 in campaign missions,
Because you need 2 more DNAs for Printing
To upgrade Basim to 3 Star DNA, you must also complete the 25th Campaign mission.
You can see the level of your Campaign heroes according to this table published by
Dear Rob(One of ACR Official Discord Channel Moderator) on the ACR Official Discord Channel:
For example, to upgrade Valka to 3 Star DNA, you need to complete Campaign Mission 20.
But to upgrade Basim to 3 Stars, you need to complete the 25th Campaign mission