Not able to reduce storage (plan)

Hi!

I am currently paying 29 SEK a month for a 200 GB storage plan for an Apple Id i am not even using anymore.... I am trying to reduce storage but the only alternative is to reduce plan to 5GB = 9 SEK a month... It is not applicable to choose the Free alternative. I really don't want the current plan to be re-newed in january, what should i DO? Also i do not want to pay 9 sek a month i want the free storage plan since the account is not even active anymore...

Kr

Hanna