Lost Requests for api EC2 with ALB

Hello.

Deregistration delay is a parameter that specifies the period during which new requests will not be accepted when an instance is removed from a target group.
Therefore, it is unlikely that requests will be terminated even if this setting value is changed.
https://docs.aws.amazon.com/elasticloadbalancing/latest/application/load-balancer-target-groups.html#deregistration-delay

Is it possible that the ALB timeout is related?
https://docs.aws.amazon.com/elasticloadbalancing/latest/application/application-load-balancers.html#load-balancer-attributes