Why isn’t my availability reflected in the crewing numbers?

Make sure you have the correspondent skills enabled for that station.

Hover your mouse over your rota and you'll see the all the skills you have enabled:

Every time you see your name in the system with a dotted underline, you can click it and it will show a pop up also with a summary of your skills across the system:

Also you can go to your profile and see same info:

And lastly, together with your manager (or someone with supervisor rights) you can review your certifications (skills) per station by going to the Users item in the menu and then selecting "Skills" option.

And there you'll see a table of available skills in the station and all people in station

Blue boxes mean you have that skill enabled.

NOTE: If your station (or service) is using the Firefighter skill for the crew numbers, note that this does not have an abbreviation, so it does not show next to your name or elsewhere. You or your manager need to go to Users -> Skills to manually check if you have it