Child Tax Credit - Is this right?

[GrumpyOldHorsewoman]

The other day I got a letter saying my Child Tax Credit would be stopped because I hadn't replied with our details (I had tried in vain to phone them many times). Anyhoo, rang them the other day with the details off our P60s. Girl on phone told me too late to re-start - we would have to re-apply, but that she would update our info.
Then...this morning got a credit into my bank account for £1026.23 for 'child tax credit'. Should I be wary of this, could it be wrong? We were only getting about £70 per month over the last couple of years and I am suspicious that this is a mix up and that we will receive a demand for it back plus interest in 3 months time. Anyone else have experience of this?

Put it in a seperate account, do not touch it - and get in contact with them, by phone AND in writing (recorded delivery)

Could be that they have either paid you a year's worth at once, or they underpaid you last year, but don't touch it til they have confirmed IN WRITING that it is yours.

I got this about 900.00 when reclaimed it went into bank only a few days after too

they told us it was backdated money that they had underpaid us by all year x

Yep put it in bank account0- a high interest one so you will gets ome benefit LOL! then phone them (warning: took blardy ages to get through today!) and request a breakdown to be sent immediately.

It might be yours you know, we found about £1800 we're owed through wrongly inputr details (all DLA stuff) and succesful apepals today, it may be your lucky day as well?