When someone asks for forgiveness, forgive them as you would want to be forgiven. Not one of us is perfect, we all make mistakes.
Peter once asked Jesus: «Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?»
Jesus answered: «I tell you, not seven times, but seventy times seven» (Matt 18:22).
Therefore, forgive generously and you shall be forgiven generously. Sow what you would like to reap.