I ask this question from comment of this answer by @MooS on Why was Obi-Wan was so confident about Count Dooku? Was he arrogant?
Palpatine uses the force to make Obi-Wan unable to defend himself, since he wants Anakin to beat Dooku. Obi-Wan cannot block this since he does not suspect it at all.
Did Obi-wan ever try to understand why he failed at that time or did he assume that he was no match for Dooku or did he simply ignore it and move on?