You use encryption (https). Your use of https encryption is exempt, or, more precisiely, it is not a not-exempt use. More recently regulations actually require you to submit documentation for exempt https encryption - but many many developers are ignoring that requirement and nothing seems to be happening.
When you submit the app you will be asked two questions. I do not recall the exact yes/no but you will answer the first question in a way that causes you to be presented with the second question. (e.g. 'yes' I use encryption but 'yes' it is exempt' or 'yes' I use encryption but 'no' it is not 'non-exempt').
You can also do this through an info.plist entry as described here:
https://developer.apple.com/documentation/security/complying_with_encryption_export_regulations?language=objc
I do not recommend the plist approach for a very nuanced reason. Action A - Answering the two questions honestly and then failing to submit a report is IMHO argueably a minor disgression. Action B- Answering the first question falsely to avoid the second question may not be a minor transgression. Using the plist approach and failing to submit the report may argueably be interpreted as pursuing Action B rather than Action A.