Requesting message to Bing help

I have indexed a site named getandroidapps4free.blogspot.com  ,, it was working fine.. but I have just purchased a domain named: appsapkfreedownload.com and verify it to bing webmaster tool,, but the problem is arising that in this time when I am submitting my sitemap as http://appsapkfreedownload.com/sitemap.xml it is not validate and showing me 404 ,, as a result the site is not indexing in bing. But my sitemap is showing on previous site http://getandroidapps4free.blogspot.com/sitemap.xml
What should I do? I can't understand what to do?  I need to resolve the problem ASAP. Please give me a solution.
Thank you