Tax Rebate.

On the advice of a neighbour who had done the same thing, I recently claimed a rebate called Marriage Allowance against my husbands tax. Filled in all the appropriate details and was told immediately I would receive a cheque for around £212 for the period April 2015 - April 2016. This was 3 weeks ago and I've not received a thing. Meanwhile, husband has had a letter saying they owe him £209 as his tax code had changed and we could apply online to get it within 3 days. After 2 hours of trying to do this we gave up and tried phoning them instead. This was even harder work and still no joy. They certainly don't make it easy. Anyone else had this?