Thanks for the query.
There is possibility of some hormonal imbalance.
So you once consult gynecologist and go for blood test
If the test comes negative, go for ultrasound
By this possible causes like poly cystic ovary disease etc can be made out.
Then with your doctor's advice, you can take tablets for withdrawal bleeding.
In the next cycle, go for ovulation induction
and try for pregnancy.
For more details you can ask me directly through the premium forum.