Ebay api find fault and fix it.

we sell items through our website and also through ebay. items are uploaded to our website and then uploaded to ebay using ebays api.
this worked perfectly previously up to a couple of week ago when i tried to upload items to ebay and it does not seem to be working.
on my website admin bulk upload to ebay is showing as complete as though everything is done but nothing is showing up in our ebay shop.

so all i am looking for is for somebody to have a look find the fault and fix it. that is all.
if this goes well there may be more work from me.
hopefully i have explained what needs to be done clearly but if there is anything else please do not hesitate to contact me.