Feed has no items with valid RSS feed

Hello,

I have a problem on a new domain with my page. I used your plugin since a year without any problem. I have an other page too and on there, the plugin works properly.

But in the new domain, I getting the Feed has no items errors again and again. I checked my feeds with the validator, and both of them is a valid RSS feed. I am using the same settings on this new page as in the previous one. I tried an other plugin, and the same feed worked with it, so my feeds are correct.

Do you have any idea what would be the problem?

Thank you! Pete