My girls back two nipples are quite flat and pups are having trouble feeding off them, so they don't bother, they are both very full and getting hard which is a worry, whats the best thing to do ?

Thanks

This happens every time with one of my girls, try the hot flannel -  not boiling obviously ;-) on the two back ones, hopefully it should soften them a bit, but do keep an eye out for mastitis,  if they get really hard and uncomfortable and purple looking get her to the vet, she may need anti-biotics

Thank you Sharon.  I have been putting a warm flannel on, and fighting to get the pups on it, they are fiesty little things even at 48hrs old they know what they want !!
Have had them feed off the back ones three times over night, she is sleeping now as soon as she wakes up I will check her again.

Keep up the hot flannel - as hot as the bitch can take, and make sure the strongest ones work the teats to get them going.