DescribeInstanceTypes fails with access denied for some AWS regions

Question

I'm trying to get the Instance Details with the Amazon go SDK.

However, I'm getting this error for some regions.

AuthFailure: AWS was not able to validate the provided access credentials ...

A search on that error reveals that I need to do something different with the credentials. https://aws.amazon.com/premiumsupport/knowledge-center/iam-validate-access-credentials/

It's not entirely clear what I'm meant to do as there are no examples that I can find that do this in go.

How do I modify the below code to remove the error?

func (service *CloudClusterInfoService) AmazonEksFetchInfo(accessKey, secretAccessKey string) (*AmazonEksInfo, error) {
    log.Debug("[cloud] [message: sending cloud provider info request] [provider: amazon-eks]")

    resolver := endpoints.DefaultResolver()
    partitions := resolver.(endpoints.EnumPartitions).Partitions()
    eksInfo := &AmazonEksInfo{}

    for _, p := range partitions {
        // Get a list of regions where the Amazon EKS service is available
        if eks, ok := p.Services()["eks"]; ok {
            for _, region := range eks.Regions() {
                eksInfo.Regions = append(eksInfo.Regions, portaineree.Pair{
                    Name:  region.Description(),
                    Value: region.ID(),
                })

                log.Infof("Region: %s, URL: %s", region.ID(), endpoint.URL)

                sess, err := session.NewSession(&aws.Config{
                    Region:      aws.String(region.ID()),
                    Credentials: credentials.NewStaticCredentials(accessKey, secretAccessKey, ""),
                })

                if err != nil {
                    log.Errorf("[cloud] [message: failed to create AWS session] [provider: amazon-eks] [region: %s] [error: %s]", id, err)
                    continue
                }

                svc := ec2.New(sess)

                params := &ec2.DescribeInstanceTypesInput{
                    Filters: []*ec2.Filter{
                        {
                            Name:   aws.String("current-generation"),
                            Values: []*string{aws.String("true")},
                        },
                    },
                }

                types, err := svc.DescribeInstanceTypes(params)
                if err != nil {
                    log.Errorf("[cloud] [message: failed to get instance types] [provider: amazon-eks] [region: %s] [error: %s]", id, err)
                    continue
                }

                for _, v := range types.InstanceTypes {
                    fmt.Println("Instance Type: ", *v.InstanceType)
                }
            }

        }
    }

    return eksInfo, nil
}