BeatnicksBaton lambert

I just went to pay my tax bill for 2021/22 and paid the amount of £1000 that was shown then when I checked my calculation it gave an amount higher than that. My wife has also paid her bill tonight and was prompted to pay the full amount that was calculated, as we'd expected. Any idea why I'd be shown a lower amount than I believe I owe, and how can I pay the rest now?

Hello, I'm in a SMART pension scheme where my pension contribution is deduced from my gross salary therefore My P60 shows a gross pay of less than £50k as it's been reduced by my pension contributions. Should I add these contributions back to work out my adjusted net income as this would take it over £50k?