As your parents are worried about you, you should call them more often.
※be worried about … …について心配している
Your parents are concerned about you, so you may as well give them a call more frequently.
※be concerned about … …について心配している may as well ~ ~した方がいい give 人 a call 人に電話をする
must ~(~しないとだめ)
more often(もっと頻繁に、more frequently)