Yesterday one of my clients asked me a question and I replied to his email but today he again repeated his request and I understood that yesterday I've got it wrong.
Therefore I now need to assure him that I was able to understand him after that he provided more explanation about his problem. How can I say that I was confused yesterday but I got it today?
For example something like this:
Hmm, Now I grasp what you said ... (but very formal)