Brief Answer:
Erection failure

Detailed Answer:
Hello

Thanks for the query

Erection failure is very common in men, most of the times it is reverses on its own without any treatment. Some of the common causes of erection failure are

1. Stress and lack of sleep
2. Smoking and alcohol
3. Sexual boredom
4. Drugs like beta blockers
5. Anxiety to perform sexually
6. Obesity
7. Spinal injury
8. Hypertension, Thyroid disorder and Diabetes

Here is what I recommend you to do

1. Avoid masturbation for a week
2. Sleep on time and eat healthy foods
3. Exercise daily for atleast 30 min
4. Avoid smoking and alcohol
5. Visit your GP to get checked for Hypertension, diabetes and thyroid disorders
6. Tab Sildenafil is a wonderful drug to get a sustained erection , approach your doctor for a prescription

I hope I was of help

Regards

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