Why am I unable to add a NAT rule with a specific port range?

Zyxel_Kevin

Why am I unable to add a NAT rule with a specific port range?

Question: Why can't I add a NAT rule for the port range 51000-52000 on my firewall?

Answer: 

The issue arises because of overlapping port ranges in your existing NAT rules. Specifically, RuleX is already using the port range 49152-65535, which overlaps with the new port range you want to set up (51000-52000). 

In order to add your desired NAT rule, you need to modify or remove the overlapping port range in RuleX.