It is very common for an 8 month old baby to not be interested in nursing. She needs to be getting at least 4 milk feeds until she is 10 months old.
You can try changing her nursing pattern, like feeding her as soon as she wakes up and is still sleepy, or in the middle of the cycle, or before she sleeps.
Make sure that you are only giving her two average sized solids meals or three smaller solids meals at 8 months old. If she is eating too many solids, she won't be hungry for milk.