Meter doesn't match imported measure

There were several threads. The following was maybe the longest:

If you insert a meter in a measure to be able to clean up the previous measure (without making a mess) a red flag pops up. If you then hide the meter when the situation returns to normal, Dorico keeps the red flag in place. But you can delete these redundant red flags by clicking on them, which turns them a darker red, and then pressing delete.