For a week now my hasband has been experiencing erectile problems.he gets and erection, but he doesn't keep it.he's only 30.what could be the issue?

Erectile dysfunction: The causes of erectile dysfunction may be psychological in a young man. However, other causes needs to considered including side effects of medications, sleep apnea, morbid obesity, hypertension, diabetes mellitus, vascular diseases. Etc. He needs to be seen by a urologist and undergo some testing to differentiate between psychological causes versus those related to diseases.