Trying this out!

Trying to write: I'm sorry, I don't understand in Hiragana.

ごめんなさい わかりません

Is this correct? Thanks for the input! c:

Correct! 

You are getting it right!

Or, if you want to say: I am sorry, I don't understand Hiragana.,

you can say,

ごめんなさい　ひらがな　わかりません

It's a key to add an object before the verb in Japanese. 

You are getting it all the way.

Yuki Jane