He does have a grudge because he believes Hillary interfered/unfairly called his own election into question.
Via Daily Caller:
Hillary Clinton believes that Vladimir Putin was allegedly involved in the hack of the Democratic National Committee because of a longtime grudge he has held against her.
The former presidential nominee made the claims at a party meant to thank her millionaire donors in New York Thursday night, according to two donors who were there.
They said that Clinton blamed the grudge on comments she made that were critical of Russia’s parliamentary elections in 2011, which she said were not free or fair.
Clinton told guests at her party that she was proud, as secretary of state, to have defended democracy when confronted by Putin.