While using Persistence profile utilize all backend servers in BIG IP LTM

Hi team

Any one help me regarding below requirement

one of the applications, there are four backend servers, but currently the traffic is being directed to only one pool member but want to distribute or utilize all backend servers.

The current configuration is as follows:

• Persistence profile: Enabled with Hash

• WAF SNAT: None

• LB SNAT : Automap

• LB pool method: round robin

• X-Forwarded-For: Enabled on WAF

• X-Forwarded-For: Also enabled on the LB

However, despite the above configuration, the traffic is sticking to a single pool member. The client requirement is to distribute the traffic across all four backend servers.

Application traffic flow:

Client → Firewall → WAF → LB → Backend Servers