MQTT to Dynamo DB

We have a Thing that is receiving data from and ESP32, we then want to send that data to Dynamo DB.

We've created a table, rules and policies that all worked for about 3 days and then stopped. Every now and then it works for an item or two, but very rarely. We've checked through all the policies and rules and table settings, comparing to online tutorials, but nothing has helped.

We have also created a whole new ESP -> MQTT -> Dynamo Thing set and that doesn't work at all.

We can connect, send and receive through the MQTT as well as send the data to S3.

Has anyone else experienced this, and/or knows what we should be looking at next