Bot API 429s on JMeter load test

What is the reason the Bot API is returning 429 errors when JMeter 5.6.2 hits just 5 concurrent threads? Testing against Genesys Cloud BYOC Edge 24.1.0 from Asia/Singapore.

HTTP/1.1 429 Too Many Requests
Retry-After: 10

JMeter config is standard HTTP request sampler with keep-alive. Seems way too sensitive for this thread count.