What’s wrong with my magnolia?

[Cassandra9]

Hello can anyone tell me what’s wrong with my magnolia and know how to fix it? Thanks in advance.

Greenfly. You can ignore it and they will get eaten by other creatures or you can pour soapy water on to wash them off

Thank you.
There are quite a lot of brown/black edges to the leaves. Do you think this is unrelated?

Couuld be that the edges were damaged by the green fly when they were first emerging. Not much you can do now.