Google Sheets - Arrayformula with textjoin, and, if

I'm trying to figure out how to make my arrayformula with textjoin to work, but the formula does not copy to another row.

I want the job no automatically generate when i write data in F3 cell & G3 cells.But i having problem the formula does not automatically inserted to I3.

My formula looks as following right now:

=ArrayFormula(IF(AND(ISBLANK(F2),ISBLANK(G2))," ",TEXTJOIN("-",TRUE,LEFT(F2,4)&ROW()-1,RIGHT(G2,2))))

Any Google Sheets pro's out there who could help me out in a direction?

Would be thankful for any help!