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After contacting GMC, we got to know that GMC implemented some additional security on 20/07/2021 due to some nefarious activity that was hitting their service.  That mitigation blocked our connection to the API. On 21/07/2021 at 11am, GMC added a whitelist to that mitigation and that resolved the problem.

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Trigger

Additional security had been added to Cloudflare's firewall due to them being attacked the previous day.

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Detection

Alert in monitoring channel:

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Resolution

Comms with GMC who stated:

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Timeline

21/07/2021 at 09:40 Joseph Kelly noticed issue in monitoring channel

21/07/2021 at 10:26 Katy raised issue

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