On April 16th the Washington Post published Mr. Comey's article in which he says that “In their minds, the murderers and accomplices of Germany, and Poland, and Hungary, and so many, many other places didn’t do something evil. They convinced themselves it was the right thing to do, the thing they had to do.”
While the US ambassador already apologized to Poland over FBI chief's Holocaust remarks Mr. Comey didn't find the time to do so as well.
That only means that he is not sorry for what he said and if that is a case he should not be allowed to keep such an important position in US government.