Extremely Slow Upload Speed

I recently installed UTM 9 Essential Firewall in order to simply move my database server to its own NAT for security compliance.

Using Speedtest.net - The Global Broadband Speed Test on the database server:

- The download speed was fine (> 10 Mbps)
- The upload speed was extremely slow (< 0.25 Mbps).

The upload speed in the external network was fine, so it definitely seems to be something on the firewall that is causing the issue.

Is there a way to increase the upload speed?

Thanks,

Jon