tax credit-more then 1 claim in household issues

zam121

hi guys basically any advice please. i applied for tax credits for me/partner and 2 kids in march after waiting 3/4 months recieved a letter to say my claim had been rejected,in that time i called a number of times to be told its being processed. after recieveing rejection letter i called to ask why but was told no reason on system and to re apply. i applied again in mid augast and up till today recieved no response.called tax credits today to be told there are more then 1 couple applying from this address. which is true because my brother is claiming,and my sister.and parents but i dont see why that should be a issue.what i need to know is will my tax credits be backdated to march or augaust also how long till i recieve any money.thanks

System

It could be that Tax credit compliance are investigaing your claim because of the number of claims made at your address. However usually they would write out asking for proof of who you are and ask for copies of bills etc to your address with your names on them.
If there are several claims made using the one address and the property appears too small to hold the number of people supposedly living at that address then that looks suspicious. If your relatives are applying and don't live with you get them to use their own address.

zam121

havent recieved any kind of letters or anything, my parents and brother/sister have being getting tax credits for previous few years and are still recievig them its just my application being held up!its been 7 months and havent recieved a penny! will i get it backdated once its been checked