Production order - Availability check

Dear All,

I need help to solve the issue regarding Availability check for material components.

As shown below So many batches are available for the material in both storage locations, and there are no reservations against these batches. But while releasing Production order, System is showing Missing parts msg for this material.

And when i release the production order in spite of missing parts, automatic batch determination will take place for all materials and process continues without any issue. What is the possible reason for this?

And What are receipt reservations?

Please let me know if any additional data is needed.

Thanks,

Prasad