I am still struggling with this challenge

I am getting "IndexError: string index out of range" error

I am stuck here: 'First a of in' should equal 'First A Of In'

I am sorry but the text is not being reversed; what i can see is only the addition of a space between the words

'elbuod decaps sdrow' = > 'elbuod decaps sdrow' (only the spaces added here)

I need your help guys.

My code passes three tests until I get to the bellow

Expected: 'elbuod decaps sdrow' should equal 'elbuod decaps sdrow'

For the 4th test, my function returns "double spaced words"
If I split the above text into a list then reverse word by word then I will get the following:
elbuod = > double
decaps = > spaced
sdrow = > words

Therefore I expected the final text to be
elbuod decaps sdrow = > double spaced words

I don't understand what is required here