Too much fluid

Has anyone had too amniotic fluid?

We had a growth scan at 34w3d and baby measured in the 46% for weight. And AFI was measured in limits.

Today at 36w5d baby measured in the 76% for weight and AFI was high. One pocket measured 0.0 and the other measured 9.

We had NIPT testing done and it came back normal and the anatomy scan at 21 weeks was normal.

Doctor thinks it’s idiopathic (just a fluke) but I’m worried because it could mean heart defects, kidney problems, cleft palates ect