UnmetPlayer

I get a number of different errors when running the bot and they are always to do with the offers. This is what I have so far with the new offer for a stranger and the owner offer stuff. Just to let anyone know this bot sells TF2 Scrap for Steam Emoticons. The Code:

manager.on('newOffer', (offer) => {
    let counter = 0
    if (offer.itemsToGive.length == offer.itemsToReceive.length) {
    	for (let i = 0; i < offer.itemsToGive.length; i++) {
    		if (offer.itemsToReceive[i].type.includes("Emoticon") && offer.itemsToGive[i].name == "Scrap Metal") {
    			counter++
    		}
    	}
    	if (counter == offer.itemsToGive.length) {
    		offer.accept(function(err, status) {
    			if (err) {
    				console.log("Unable to accept offer: " + err.message);
    			} else {
    				console.log("Offer accepted: " + status);
    				if (status == "pending") {
    					community.acceptConfirmationForObject(config.identity, offer.id, function(err) {
    						if (err) {
    							console.log("Can't confirm trade offer: " + err.message);
    						} else {
    							console.log("Trade offer " + offer.id + " confirmed");
    						}
    					})
    				}
    			}
    		})
    	}
    } else if (offer.itemsToGive.length == 0){
	    offer.accept((err, status) => {
	      if (err) {
	        console.log(err);
	      } else {
	        console.log(`Donation accepted. Status: ${status}.`);
	      }
	    });
    } else {
	    offer.decline(err => {
	      if (err) {
	        console.log(err);
	      } else {
	        console.log('Donation declined (wanted our items).');
	      }
	    });
    }
});
//owner send trade, bot instantly accepts
manager.on('newOffer', (offer) => {
	if (offer.partner.getSteamID64() === config.ownerID) {
		acceptOffer(offer);
		console.log("Successfully accepted")
	} else {
		delcineOffer(offer);
	}
});

Some examples of errors I get, "Cannot read property 'partner' of undefined" that error is from the owner code. Then when removing that code the bot works, but it means I cannot send trades as the owner with out logging onto the bot's account and accepting it manually. 

I hope someone can help me.

Thanks

Unmet