The packet does not match any existing firewall policy and therefore matches the implicit deny rule action="deny" policyid=0.
Likely your existing firewall rules are not matching for the src/dst and ports seen in the log entry.
It is very unlikely this issue could be resolved through the forums without knowing your policy framework.
It's recommended to open a support ticket with technical support to have this further investigated so you can share your config for review.
The first steps here would be to collect a debug flow and check the config file.