Summarizing the discussion as an answer below so it benefits others in the community seeing similar issues.
@Iain Harris @Rowland Shaw We had gotten similar reports from other customers today about this error. It appears that this was caused due to an ISP issue in the region, and is now resolved. More details here: https://twitter.com/ealexhudson/status/1434921204289351683
Please check if you are able to access your apps again as usual.
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