no sperm once in awhile during ejaculation.

There is a disorder called retrograde ejaculation in which the sperm enters bladder instead of leaving the body through urethra. You know that bladder is usually closed during ejaculation but in this condition, it doesn’t close properly and sperm ends up in bladder.
This is not harmful. I suppose you are not thinking of having any more children () as it might impair fertility.
You didn’t say anything about your general health and if you had any medical conditions as there are some that could be the cause of your periodical lack of ejaculate.
The most common diseases associated with retrograde ejaculation are diabetes and multiple sclerosis but it could also occur after prostate or bladder surgeries, or due to certain medications like hypertension drugs, psychiatric drugs or due to prostate enlargement.
You may decide to see an urologist to see if there’s an underlying condition.

Is theres a Cure or treatment, im alot younger man with diabetes and me and my wife would like to bear a child one day

I have the same condition. I was diagnosed with diabetes (115 mg/l bloodsugar). Of course, this is not really serious yet, but it is a condition I might have retrogade ejaculation. I'd like to know if there's a cure for this problem, other than surgery?

I am an older man. When I masturbate, I do not ejaculate. Is this a medical problem? Can it be corrected?