pug champ broke for me :(

TypeError: Cannot set property 'low' of undefined
at userSchema.set.transform (/home/server/pugchamp-dev/database.js:71:40)
at model.Document.$toObject (/home/server/pugchamp-dev/node_modules/mongoose/lib/document.js:1875:19)
at model.Document.toObject (/home/server/pugchamp-dev/node_modules/mongoose/lib/document.js:1998:15)
at /home/server/pugchamp-dev/modules/common.js:70:54
at Layer.handle [as handle_request] (/home/server/pugchamp-dev/node_modules/express/lib/router/layer.js:95:5)
at trim_prefix (/home/server/pugchamp-dev/node_modules/express/lib/router/index.js:312:13)
at /home/server/pugchamp-dev/node_modules/express/lib/router/index.js:280:7
at Function.process_params (/home/server/pugchamp-dev/node_modules/express/lib/router/index.js:330:12)
at next (/home/server/pugchamp-dev/node_modules/express/lib/router/index.js:271:10)
at /home/server/pugchamp-dev/modules/common.js:66:9
at Layer.handle [as handle_request] (/home/server/pugchamp-dev/node_modules/express/lib/router/layer.js:95:5)
at trim_prefix (/home/server/pugchamp-dev/node_modules/express/lib/router/index.js:312:13)
at /home/server/pugchamp-dev/node_modules/express/lib/router/index.js:280:7
at Function.process_params (/home/server/pugchamp-dev/node_modules/express/lib/router/index.js:330:12)
at next (/home/server/pugchamp-dev/node_modules/express/lib/router/index.js:271:10)
at SendStream.error (/home/server/pugchamp-dev/node_modules/serve-static/index.js:120:7)

Anyone know what this means? THANKS