This is caused by the corresponding Gateway Firewall Rule being logged having matched criteria in the flow and applied to the same interface at the DNAT/SNAT rule.
Check to see if this correspondence is correct by logging into the Edge and running command 'get firewall <UUID> connection'
Example shows in a live flow format and the rule id will matched with the corresponding DNAT rule [Gateway Firewall Rule ID = 11252] & [DNAT Rule ID = 536870915]
0x020079bd2c000f26: ##.##.##.#:37894 -> ##.##.##.#:22 (##.##.##.#:22) dir in protocol tcp state ESTABLISHED:ESTABLISHED fn 11252:536870915
Example or rule settings shows rule 11252 is set to logging
Resolution
Use command 'get firewall <UUID> connection' to get a live connection flow and match rule id to corresponding DNAT/SNAT rule.
Additional Information
Troubleshooting, Logging information, and Commands for Edge Firewall. Follow steps to get the proper UUID for command 'get firewall <UUID> connection' Troubleshooting Gateway Firewall