Does Not Work Sync With VRBO and Airbnb

I’ve been a VR Cal user for over a year and have never got the sync function to work with VRBO and Airbnb. I finally got angry and contacted the customer service (no phone–only email). I have received 17 emails from their customer service rep over piddly crap “did you try “sync” on the plug-in”. I have not received any help. The customer service is awful based on my experience if it even exist. I worked with an hour with VRPO tech and they said the problem is VR Cal not transferring the data.
If anybody has had success getting the “sync” function to work properly, please respond. My expectations are that when I populate my calendar on my website, the calendar on VRBO and Airbnb would automatically populate. Are my expectations correct? This seems so simple. VR CAl says their program follows iCal protocol (same as VRBO and Airbnb) but it doesn’t seem to work
Pardon my venting