I have to guess the failure is one of the two memory sockets. There is no supported repair except to replace the board. I hope someone gives you the cost since it will help you choose your next step.
Bob
My Macbook only has one memory working according to MAC repair center. Technician said he increased the one side memory and suggested I use it as is.
Should I get the other memory fixed before I pick up my laptop or will it work fine with an increased one memory side?

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