Having struggled my way through conjugating sonkeigo, I’m now tackling kenjougo. I understand when to use it, but differentiating between when to use お。。。いたします vs お。。。します is confusing me.
For example, why are both these correct:
お荷物を持ちいたしましょうか?
お荷物をを持ちしましょうか?
But in this example only します is correct:
これをお渡ししてください。
And in this example only いたす is correct:
品物は明日お送りいたします。
Any help would be appreciated! My current understanding is that お。。。する is less humble, but I don’t get why sometimes both answers are accepted whilst other times it’s one or the other.