How long before phone verification disappears when trying to create a new account?

Hello. So yesterday on a private proxy I created a new Facebook account with no problem. Today (about 20 hours later) I tried to create another Facebook account on the same private proxy but it asked me for the phone verification. Keep in mind that I didn't do anything on the first Facebook account. I didn't message anyone, add friends, join groups, etc. All I did was update my profile like what tv shows I watch, a few wall posts, etc. It is also worth mentioning that I can log into this first account with no problem. It doesn't ask me for phone verification when I try to log into it. It just asks me for phone verification when trying to create a second account...

What is the refresh time on this phone verification going away when trying to create a new account? I remember on another proxy I got this phone verification when trying to create a new account, then tried again the next day and the phone verification vanished. So I am assuming there is some kind of cool down? Anyone know what it is?

Thank you.

usually around 24 hours, however make sure all your cookies etc are cleared

Dude now days very very hard to create facebook accounts. . must be use unique IP per accounts if u need then clear all cookies and browser history