Forfeiture amount per share is the amount to be received by the company on forfeiture of each share.
$$Forfeiture\quad Amount=Application\quad Amount\quad +\quad Allotment\quad Amount$$
Substitute the values in above equation
$$Forfeiture\quad Amount=Rs2$$
Forfeiture amount is the money received by the company on forfeiture (cancellation of share) or on the reissue of share.
$$Forfeiture\quad Amount= No.\quad of\quad shares \times Forfeiture\quad Amount$$
Substitute the values in the above equation
$$Forfeiture\quad Amount=10shares \times Rs2= Rs20$$
$$Forfeiture\quad Amount\quad for\quad 8shares=8shares \times Rs2=Rs16$$
$$Forfeiture\quad Amount\quad on\quad reissue=\quad 8shares\times Rs0\quad = Rs0\\ $$
The extra 1 rupee paid by the shareholder on the reissue is not considered because it is a part of the security premium, not share forfeiture amount.
Profit on the reissue is the profit earned by the company when the forfeited shares are reissued
$$Profit\quad on\quad reissue=Forfeited\quad Amount\quad on\quad forfeiture\quad -\quad Forfeited\quad Amount\quad on\quad Reissue$$
Substitute the values in the above equation
$$Profit\quad on\quad reissue=Rs16-Rs0 = Rs16$$
Hence, the profit earned on the reissue of shares is Rs $$16$$.
Share forfeiture a/c Dr. Rs16
To share forfeiture a/c Rs16.