Hello @Frank Cort
Thanks for reaching out!
Error 503 comes when 'The service is temporarily unavailable for maintenance or is overloaded. You may repeat the request after a delay, the length of which may be specified in a Retry-After header'. Refer this documentation. You can retry the requests or increasing the timeout (Incase you are using any custom application increase the timeout for at least 2 min).
Another reason could be likely because the services are busy. You should employ a back-off strategy similar to 429. Additionally, you should always make new retry requests over a new HTTP connection. Refer this documentation.
Hope this helps!
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