Object store key pointing to null even though it actually has a value

Question

I am processing some few thousand records using batch, before sending records to batch, I'm storing the key : value in object and retrieving them and processing, but for some records I'm facing the error.

'org.mule.extension.objectstore.api.TopLevelObjectStore$EnhancerByCGLIB$1f51aa05@1448fb70' doesn't contain any value for key '21725' and default value was not provided or resolved to a null value.",

Can someone please help me solve this problem

this is my flow and config setting of object store.

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