i never get support money since 1 Year.
Do you mean item support money?
have you received any extended support purchase from any customer? check your Statements page. you will get all purchase info there. For each purchase first 6 months support is free with the purchase but if your customer extend the support period (purchase) only then you will get payment for the extended support.
Check your item support settings and make sure it’s enabled
themeforest.net/user/ USERNAME /item_support_preferences/edit
why first 6 months support is free if i didn’t get it.
You should to check your statements first. free for customer because this first 6 months support included with purchase. but you will receive payment. for each purchase you will get 4 invoice 2 for your earnings where 1 for license (as like regular license) sold and 1 for 6 months included support. and another 2 for your author fee.