Question
If you pray Surahs in wrong order do you have to do sijda sahw
Answer
No it is makrooh to do so, therefore sajdah-e-sahw is not wajib.
Sajdah-e-sahw is only wajib if a wajib act it is missed out or a fardh is moved out of its place.
Sajdah-e-sahw is not wajib due to a makrooh act however the reward of the salah will be decreased.