Bucket4j rate limiting based on user with complicated condition

Question

I have 2 requirements need to be fullfilled:

1. Apply rate limiting for an @GetMapping API based on user: only 15 requests per minute per user. Quite simple! I create a concurrent hashmap<username, bucket> to group buckets by user. Any request comes, I will get username, then get the corresponding bucket, then apply rate limiting.
2. Apply rate limiting for an @GetMapping API based on user and a @RequestParam "transaction-id": If same user call this API with different transaction-id, limit up to 5 requests per hour per user. If same user call this API with same transaction-id, then (1) will be applied. For example:

   invokeAPI("ey12==", "t1") OK,
   invokeAPI("ey12==", "t2") OK,
   invokeAPI("ey12==", "t1") OK,
   invokeAPI("ey12==", "t1") OK,
   invokeAPI("ey12==", "t3") OK,
   invokeAPI("ey12==", "t1") OK,
   invokeAPI("ey12==", "t4") OK,
   invokeAPI("ey12==", "t5") OK,
   invokeAPI("ey12==", "t6") Blocked
   

Requirement 1 is done. Please suggest me a solution for requirement number 2. Is Bucket4j suitable for this case? I event don't know where to start at.