Failed to invoke procedure `apoc.merge.relationship`: Caused by: java.lang.NullPointerException

i got this problem when i try to merge relationship for >10 nodes. It only works if it is below nodes to merge relationships for.

Neo.ClientError.Procedure.ProcedureCallFailed: Failed to invoke procedure apoc.merge.relationship: Caused by: java.lang.NullPointerException

I searched and notice other ppl had similar problem but with other APOC procedure, however there seems to be no solution.

i did tried to set config such as apoc.import.file.enabled=true etc. but no use.

would appreciate if anyone could suggest a fix? thx

Can you provide the exact query?

Thx Andrew. I figured out the problem: it cannot have null value in the relationship.