Hey! I Took Primolut For 6 Months , My Periods

Hey!
I took primolut for 6 months , my periods were obviously regular during the medication but When I left it and got my periods once. And its been 4 months i didnt get my periods after that. And i have been gaining weight. Should i start primolut again?
Does prinolut cause weight gain?
And if i start primolut and workout would it keep the weight balanced?
Please let me know
Thankyou