The EXACT same thing happened here a few weeks ago..., which would coincide perfectly for the same age your DD is now.
It was really frustrating, I just tried to offer it to him more hoping that he was getting enough... but he seemed to be (wet & dirty nappies) and he was happy enough in between feeds.
He was exactly the same - night feeds were fine & the same length as usual, no fuss.

Carmelo went through it for about 1-2 weeks and seems to be back to normal now.
I have no idea why (the other girls are more knowledgeable than me!) but I do know it was a phase