[More Question] How to use ‘PURGE’ and ‘PURGE_URL’ Method in F5 DoS products

Hello. My name is Kim. 

I would like to ask additional questions because I did not get the answer I wanted from the link I previously asked.

Link to existing inquiry : https://community.f5.com/t5/technical-forum/how-to-use-purge-and-purge-url-method-in-f5-dos-products/m-p/322913#M272468

Additional  inquiry : 

- In addition to how to modify iRules, we additionally checked how to allow the "PURGE" and "PURGE_URL" Method on the http profile and applied it as follows.
- Move custum-http profile -> Enforcement - Known Methods - Add PURGE, PURGE_URL to Enabled Methods -> Update
- When testing after setting as follows, it was expected that only the list of Enabled Methods would be allowed, but the result was that all other Unknown Methods were also allowed.
- Please give me advice on how to solve this problem.

Thanks.