Any help with UC deductions when working?

[PinkBarbieJet]

So for every £1 I earn from working, my Universal Credit payment goes down by 55p. I’ll earn roughly £650 a month from working, my work allowance is £404 a month and my monthly UC payment is £4129.

Does this mean that the calculation is £650 - £404 = £246. £246 x 0.55 = £135.30. So £135.30 is deducted from £4129 which means my UC will be £3993.50 a month?

OR

Does this mean that the calculation is £650 - £404 x 0.55 = £427.80. So £427.80 is deducted from £4129 which means my UC will be £3701.20 a month? TIA as I’m not sure what the correct one will be

The first calculation is correct but work allowance should be £411 (since April 2025). £404 is 2024-25

£650 - £411 = £239.00
£239 x 55% = £131.45
£131.45 is deducted

Thank you!!