Housing association chasing me for rent,do I have to pay?

[fireburningss]

I rent my property through a h/a in the north east.
My rent is £480 a month (which includes water rates -they pay direct to Northumbrian water )
At the moment I am working part time.
I checked my rent account (stupidity never check) and I was £700in credit
After going through my account I seen over two years two payments from Northumbrian water for £222
I rang Northumbrian water who said they couldn't discuss my account but could tell me the housing association applied for a water bill reduction as I'm on low income .
They didn't tell me
So I've been paying full water and they have the 50% discount from Northumbrian water
They told me h/a do this a lot.
So I worked out the money I had been paying when I shouldn't and deducted it
So I paid £350 rent this month (probs more than I should )
They rang saying I was £130 short and pay immediately.
I told them about the water discount and how they had been getting full water from me and the payments from the water company.
They said the money from Northumbrian water just builds credit on my rent but the water company said it's to help me out ,so I don't have to pay as much.
Is this correct ?

@GetyourheadoutoftheovenIris She IS paying and as you said yourself you dont have any experience of social housing

Oh yes they can. The fact you are in credit is irrelevant, the rental amount is due in full in the date stated in your tenancy agreement. If you fail yo pay they can start the eviction process after whatever time period is stipulated in your contract.

The credit is irrelevant because it isn't related directly to the rent and is applicable only to the reduction in the water rares they have applied for.

Legally you have to pay in full.

You then need to do a freedom of information request related to the coat of the water rates and handle that separately.

My tenancy agreement states a weekly amount of rent.
My account is in credit by over £700
They could evict me for not paying rent and being in arrears
I am not in arrears
This is the issue

Also checking my tenancy agreement it says they can start the eviction procedure after 8 weeks of arrears
Not 8 weeks of not paying your exactly monthly amount

We are HA tenants. Our rent is calculated weekly which is a PITA when we are paid monthly. We took the weekly figure, divided it by 7 for a daily amount then multiplied by 31 (max days in a month) and then rounded up and paid as a monthly standing order, so we over pay every month, more so on months with 30 (or 28) days.

Each time our rent account gets too much in credit, they call us to process a refund, as they don't like a big credit building up. The last refund we had was just under £2000.

Could you call and without mentioning the water payments, say that you've become aware your account has a large credit and are you able to have a refund for the over payments?