its been very warm has it had enough water, is it planted in acid or alkaline soil and finally is it in a pot or the ground, sorry to answer your question with a question but any of these could help us identify the problem problem , if not let us know again

Yes I have been watering everyday. It is planted in ericaceous compost in the ground.

difficult to say then, sorry, maybe now its cooler it will pick up, I notice you're east midlands the postman said that there was a ground frost this morning ?, maybe too cool if its been kept protected before you got it

Thanks Pamg.