'data' has bad type; expecting string, got boolean

dropbox_exception_stacktrace.js

"exception": {
  "*message": "'data' has bad type; expecting string, got boolean",
  "Exceptionstring": "",
  "*code": 0,
  "*file": "(path)/inc/lib/dropbox/lib/Dropbox/Checker.php",
  "*line": 22,
  "Exceptiontrace": [
    {
      "file": "(path)/inc/lib/dropbox/lib/Dropbox/Checker.php",
      "line": 47,
      "function": "throwError",
      "class": "Dropbox\\Checker",
      "type": "::",
      "args": [
        "data",
        false,
        "string"
      ]
    },
    {
      "file": "(path)/inc/lib/dropbox/lib/Dropbox/Client.php",
      "line": 566,
      "function": "argString",
      "class": "Dropbox\\Checker",
      "type": "::",
      "args": [
        "data",
        false
      ]
    },
    {
      "file": "(path)/inc/lib/dropbox/lib/Dropbox/Client.php",
      "line": 404,
      "function": "chunkedUploadContinue",
      "class": "Dropbox\\Client",
      "type": "->",
      "args": [
        "DXm7xX_UhOdtBZ424C4r0A",
        41943040,
        false
      ]
    },
    {
      "file": "(path)/inc/lib/dropbox/lib/Dropbox/RequestUtil.php",
      "line": 229,
      "function": "Dropbox\\{closure}",
      "args": []
    },
    {
      "file": "(path)/inc/lib/dropbox/lib/Dropbox/Client.php",
      "line": 405,
      "function": "runWithRetry",
      "class": "Dropbox\\RequestUtil",
      "type": "::",
      "args": [
        3,
        []
      ]
    },
    {
      "file": "(path)/inc/lib/dropbox/lib/Dropbox/Client.php",
      "line": 350,
      "function": "_uploadFileChunked",
      "class": "Dropbox\\Client",
      "type": "->",
      "args": [
        "/60 Retro Figures.zip",
        {
          "Dropbox\\WriteModeextraParams": {
            "overwrite": "false"
          }
        },
        0,
        null,
        4194304
      ]
    },
    {
      "file": "(originating file)",
      "line": 73,
      "function": "uploadFileChunked",
      "class": "Dropbox\\Client",
      "type": "->",
      "args": [
        "/60 Retro Figures.zip",
        {
          "Dropbox\\WriteModeextraParams": {
            "overwrite": "false"
          }
        },
        0
      ]
    },
    /* ... */
  ]
}