Hello Nelly,
Nice to hear from you again.
You have to keep in mind that you are allowed to travel to another EU-country for a maximum of 90 days within a period of 6 months. It doesn't matter how many times you traveled there, but the total amount mustn't be higher than 90 days.
As an example: You are not allowed to travel there for 89 days, return to the EU-country that issued your residence permit for a couple of days, and then travel to the same country again for another 89 days. In this case you would only be allowed to travel there for 1 more day.
If you've been there for a total amount of 90 days already, you have to wait till the 6 months period is over. Afterwards you are allowed to stay there for a maximum of 90 days again.
Best regards,
Thorgen