why my account got banned after i joined waves signature campaign?
You've likely been spamming.
i post reasonably constructive post (about 4 to 5 lines ) and my post has a time interval every two to three hours.
Neither of which has anything to do with constructive posts.
How about you post the link of your main account in order for us to check it out? Also, you've already committed the act of ban evasion by posting outside of this section whilst being banned:
campaign application.