I have a few of these small trees (i think it is Terminalia bellirica but imns) and their leaves are infested with some kind of insect. I thought they will go away on their own but they are not going away. It has been a few years now. Can some one please help me identify this menace and how to eliminate it. I have already tried neem oil spray, soap spray, but it has not worked.

Please help.

The following pic shows that this insect builds some membrane on top of the leaf. I pierced it by finger nail but couldn't see anything moving inside.

The following pic shows the leaf from the underside.

All leaves are affected.

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