Can’t get past config

I’ve followed the instructions here: https://deliciousbrains.com/wp-offload-s3/doc/quick-start-guide/ but when I look at the settings page for the plugin, the media tab is still telling me to define my accesskey and secretkey in wp-config.php which I’ve already done. I created an IAM user exactly according to the instructions. There is no clue anywhere I can find to determine what the problem is.

Thanks for any advice.