Internal Server Error

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Error stacktrace
TypeError: Cannot read property 'pages' of undefined
    at Chapter (webpack-internal:///9469:27:15)
    at d (/var/app/current/node_modules/react-dom/cjs/react-dom-server.node.production.min.js:33:498)
    at bb (/var/app/current/node_modules/react-dom/cjs/react-dom-server.node.production.min.js:36:16)
    at a.b.render (/var/app/current/node_modules/react-dom/cjs/react-dom-server.node.production.min.js:42:43)
    at a.b.read (/var/app/current/node_modules/react-dom/cjs/react-dom-server.node.production.min.js:41:83)
    at exports.renderToString (/var/app/current/node_modules/react-dom/cjs/react-dom-server.node.production.min.js:52:138)
    at eval (webpack-internal:///6249:1361:60)
    at processTicksAndRejections (internal/process/task_queues.js:95:5)