spring-cloud-zuul-ratelimit: Unable to match serviceId and routeId

rateLimit version 2.4.1 Here is my yml configuration.

ratelimit:
    key-prefix: ${spring.cloud.client.ip-address}:apiserv_rate_limit
    enabled: true
    repository: REDIS
    behind-proxy: true
    default-policy-list: #optional - will apply unless specific policy exists
      - limit: 10 
        quota: 1000 
        refresh-interval: 2000 
        type: 
          - url
    policy-list:
      cloud-currencyBackend:
        - limit: 10
          quota: 1000
          refresh-interval: 60
          type: #optional
            - url=/backend/currency/**
routes:
    cloud-currencyBackend:
      path: /backend/currency/**
      serviceId: currency-service
      stripPrefix: false

Every time while RateLimitProperties.getPolicies(key) execute , the key will be routeId likes /backend/currency/**. My policyList is serviceId : targetPolicy likes cloud-currencyBackend: some policy. Therefore the result of this method will always be defaultPolicyList.

How can I make this work ?