Metro Calendar app not Syncing with Outlook.com

I have been using Outlook.com calendar to keep all our family appointments and my business trips in one place so we can each access what is going on from our various PC's and smarthpones and this has worked fine for around 6 months.  Recently however, items that I have been putting onto the Metro calendar app on my PC are not appearing either on my iphone, other family PC's OR outlook.com calendar (via the web).  Items put on by my wife on her PC are uploading fine (also on the Metro Calendar app).  Any ideas what is going on and how I can fix this?