GetServiceQuota() for transit gateway route table returns NoSuchResourceException

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Describe the question
We are using [email protected] and we are trying to call ec2.GetServiceQuota() to get quota for transit gateway route table. From this page we found the quota code and service code for transit gateway is L-43872EB7 and EC2:
https://us-east-1.console.aws.amazon.com/servicequotas

But when we passed the correct parameters to the API, it returned NoSuchResourceException. Also, when we did a ec2.ListServiceQuotas() for EC2 service, the returned list also didn't include quota for transit gateway route table. I'm wondering if there is any ways to get this quota, and can it be related to sdk version too old? Thanks!