OAuth Token Refresh 429 during JMeter Burst Test

429 Too Many Requests on oauth/token endpoint.

Running JMeter with 50 concurrent threads on US1. The load test simulates agent login bursts. Token refresh hits rate limits immediately. Need to validate capacity for auth service.

jmeter_config:
 threads: 50
 ramp_up: 1
 loop_count: 10
 target_endpoint: /oauth/token

Is there a specific header or client_id configuration to increase the token refresh window for load testing?