Thank you for asking. I can understand you concern. Not able to retract the foreskin back easily can be a symptom of a condition known as Phemosis. It is due to tight foreskin. It is completely curable problem. With minor procedure, it can be cured. If left untreated, it can predispose towards infection and can result in discomfort while sex.
Next Steps
Kindly consult with a sexologist or general surgeon. With physical assessment and examination the doctor an decide further course of management.
Health Tips
Don't worry. It is treatable.