Hi gopalraman gopal,
The provider caches for about 24 hours or until the application is restarted/application pool is recycled. This means that articles added after you have created your feed will not show immediately.
If you can provide some steps to reproduce this issue locally we will try to find what the problem is. There are some critical fixed since 3.6 , so if you use an old version of Sitefinity, please try patching your project to Sitefinity 3.7 SP3.
the Telerik team
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