We are witnessing an increased API related errors on AWS's sa-east-1 region, due to the ongoing connectivity issue which was reported by AWS. Spot.io's users might face errors as part of various instances' provisioning as well as instances replacements, on the Spot products.
We're currently looking into it alongside AWS in order to resolve it as soon as possible.
For continuous updates, please refer to AWS status page: https://status.aws.amazon.com/
Sorry for the inconvenience and we'll be sure to update once this issue is resolved.