Tax credits hellllp!

[honey915]

I was claiming as a singleton for myself and two kids and then moved in with my partner and had to make a joint claim. I received no payments for three weeks until the claim had been dealt with. I was receiving about £185 per week whilst on smp £136 per week. And no other help. Partner doesn't work as injured but doesn't claim any help as he received compensation which is all invested into property. He makes a small amount on rental income but not alot. So I used tax credits calculator and entitled to calculator and both said we should get £165 per week and that was our entitlement for the year based on last years and this years income as I declared everything accurately. So why have they told me we can only get £28 per week. When I called they were really unhelpful! This is ludicrous! I can't even put food on the table with that! And I'm back at work in two weeks but we are really going to struggle. Any one have any words of wisdom? Thankyou!