Code Build Failed

The error does seem to be relating to account serviced quota.

Not sure how many Codepipline and CodeBuild projects you have but can you check here to see if you are exceeding the Concurrently running builds quota, among other service quotas?

There are various account level quotas that AWS sets for new and existing accounts. Some of the quotas protect you from unpredicted cost skyrocketing when you just start the cloud journey, the other ones might be applied if AWS detects something unusual in your accounts (e.g. an open vulnerability, an expired credit card, ...)

The best way to resolve this issue is contacting AWS Support and requesting the quota increase for the number of concurrent builds in AWS CodeBuild in that account. If there are some things than need to be fixed in your account first, you will be informed about that. Otherwise, the quota will be increased, so you can run your builds in AWS CodeBuild.

Thank you, This helped resolve the startBuild error. I followed the link provided by @Jason S and raised a service request increase for the compute I was using for my build, "Concurrently running builds for Linux GPU Large environment".