TypeError: Cannot read property 'isValid' of undefined

[Verize]

When creating a new trade offer I get following error:
 

TypeError: Cannot read property 'isValid' of undefined
    at new TradeOffer (C:\Users\JP\SteamBots\node_modules\steam-tradeoffer-manager\lib\classes\TradeOffer.js:19:19)
    at TradeOfferManager.createOffer (C:\Users\JP\SteamBots\node_modules\steam-tradeoffer-manager\lib\index.js:386:14)
    at SteamManager.sendSmallPotWinnings (C:\Users\JP\SteamBots\lib\SteamManager.js:327:29)
    at SmallPot.getRoundById (C:\Users\JP\SteamBots\server.js:704:11)
    at model.Query.<anonymous> (C:\Users\JP\SteamBots\node_modules\mongoose\lib\model.js:3919:16)
    at C:\Users\JP\SteamBots\node_modules\kareem\index.js:273:21
    at C:\Users\JP\SteamBots\node_modules\kareem\index.js:131:16
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

The only thing I am doing is this:

let offer = manager.createOffer(tradelink);

 

What exactly is happening here? Thanks in advance

Edited October 25, 2017 by Verize

[Dr. McKay]

What's in your tradelink variable?

[Verize]

Actually, nothing. Sorry, it was a pretty nifty mistake on my side, forgot the trade link field in my mongoose model. Works all fine now

Edited October 26, 2017 by Verize