The problem may be chewing insects rather than sucking insects. Perhaps some type of beetle or caterpillar? Look to see if you see any sign of insects. If there are small black dots, these might be excretions for the insects. You can spray with an organic control effective against chewing insects such as Bt or Spinosad. Once the leaves and flowers are damaged, they will not recover but try to control future infestation. Bt is a contact insecticide and Spinosad has a 7-10 day residual. Spray Spinosad in the early evening after the bees have returned to their hives. Once the spray has dried on the plant it is safe for beneficials. Suggest you show your photo or perhaps capture a few in a bottle as well as snip off a damaged frond for a local garden center to confirm their identity.