FT991A software bug?

When I returned to 144.174MHz FT8 earlier, the bandwidth was 500Hz maximum in digital USB. On 160m, 6m and 70cm it was 3000Hz. Now, this may be finger trouble, but I am sure that this was 3000Hz the last time I tried 2m FT8!  I am beginning to doubt my sanity. Reading the manual, I am none the wiser.

Anyone any ideas please?