UC payment early/dispute

Live in England.

So I've just received my UC March payment early with the reference Faster Pay... I don't understand why I've received it so early as my pay date falls on a weekday.

I'm also waiting to dispute the payment amount recieved (office closed on weekends) as my partner (joint claim) gets payed monthly from his work but has ended up being paid 'twice' from his work because his January job pay date fell within the assessment period and his February job pay date was the last day of the assessment period.

This has made it so his reported work earnings are twice the amount even though his January pay went on his half of all the bills, most of his February pay will be spent on his half of the bills and I (the unemployed one relying on UC for my cost of bills while searching for a job) can not pay my share of all the bills due to how much was deducted because of his reported earnings. And his February pay from work isn't enough to cover all the bills and survive until the next payment.

If anyone has advice or know what to do in this situation please let me know as I'm currently stressing over how we are going to survive the next month. Thank you