How to handle error? You cannot change the health check interval for a target group with the TCP protocol

I am trying to modify a Cloudformation template. I modified the following keys for an ElasticLoadBalancingV2 TargetGroup:

...
 InternalNLBTargetGroup:
     # https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-elasticloadbalancingv2-targetgroup.html
     Type: AWS::ElasticLoadBalancingV2::TargetGroup
     Properties:
         ...
         HealthCheckIntervalSeconds: 10
  	 HealthyThresholdCount: 2
  	 UnhealthyThresholdCount: 3
         ...
...

When I try to update my Cloudformation stack, then the update logicalId InternalNLBTargetGroup fails with status reason You cannot change the health check interval for a target group with the TCP protocol (Service: AmazonElasticLoadBalancing; Status Code: 400; Error Code: InvalidConfigurationRequest; Request ID: c46176c1-8101-4a8d-98e0-d1007c0ab019; Proxy: null)

What can I do to resolve this issue? I saw this error mentioned in the AWS docs but they didn't provide any next steps.