Not paid after maternity leave finishes

I seriously doubt anyone has been in this situation, but I am looking for advice on the off chance that any has been.

I am so grateful for maternity leave in the UK and was delighted that we can take up to a year off with our babies. That being said the statutory maternity pay gets a bit hard to live off, especially when it cuts out at week 39.

Prior to falling pregnant I had just taken on a new teaching job a few months earlier (my husband moves around a lot for work). I discovered when filling in all my paperwork that I was two short weeks off qualifying for the better school maternity pay. Although disappointed it did mean that if I decided to be a stay at home parent I wouldn't have to pay some of that money back/ commit to 13 weeks of work.

My husband and I decided pretty early on that I would not be going back to work. Teaching in the UK is stressful and I felt bad about having to put my baby in childcare for 40+ hours a week. I sent word (at the correct times)to my school that I would be returning for the summer holidays and would be leaving the school in September.

I know that I am lucky that we have been able to make cuts in our budget to ensure that I can stay home, but we were counting on and expecting my holiday pay to come through. It never did. I have contacted my school about this (they knew I expected to be paid) but they are ignoring my emails. Is there anything I can do?

We have since moved so going in in person is not possible.