Maximum send file size in SwiftSocket

I want to send a file in iPhone using SwiftSocket. But maximum sent file size is 132 kb.

I want to know this limitation is for iOS or SwiftSocket?

How can I increase file size limitation?

Code to call Send method:

switch client.send(data: myData) {
    case .success:
        return readResponse(from: client)
    case .failure(let error):
        appendToTextField(string: String(describing: error))
        return nil
    }

I debugged it. Data that sent to SwiftSocket Send method is equal the file size, and it seems it receive the file completely. I cannot find the bottleneck.