Makro deliveries always problematic - shocking customer service

I constantly have issues with Makro's courier partner WumDrop. Two out of three deliveries are not fulfilled and I get messages saying there was a problem. My latest delivery order has just had the same problem. Makro splits into multiple deliveries so the problem is multip**** by two or three. It appears that WumDrop's GPS is problematic or their drivers are not able to follow the directions. Much as I get annoyed when they call for directions, they don't do that either. Really Makro - can you not use a more reliable partner? Dealing with WumDrop is impossible because the bot says it will transfer to a "helpful agent" and nothing happens. Contacting Makro via email takes a few days. Do not call. Email only please.