de versus des

Question

Why is it "des problèmes" and not "de problèmes"

Céline Pickard · Accepted Answer

Bonjour Adelaida,
The negation in this sentence has no impact on the infinitive expression "avoir un problème" (the negation here is on "arrêter de"). Therefore, the use of "des" is correct. 
I hope this is helpful.
Bonne journée !

Céline Pickard · Answer

Bonjour Mungun-Od,
Here, the negation is with the verb "arrêter" and not "avoir". Therefore, "avoir" is not negated and "des" is correct.
Il n'a pas de problèmes. = He has no problems. 
-> "avoir" negated: de
Il n'arrête pas d'avoir des problèmes. = He doesn't stop having problems.
-> "arrêter" is negated, "avoir" is not → des
 
I hope this is helpful.
Bonne journée !

Mungun-Od Bayar · Answer

The same question for me? It is negation should be de not des