Democratic presidential candidates Sen. Bernie Sanders (I-VT) and Hillary Clinton have stopped calling each other to offer their congratulations on caucus and primary victories, according to a Sunday Politico report.

After Clinton won five states on March 15, Sanders’ campaign manager, Jeff Weaver, reportedly didn’t phone Clinton’s aide, Huma Abedin, to connect the candidates until 1:30 a.m. — after Clinton had retired for the evening. Politico reported that the call went to voicemail.

Clinton then returned the favor after Sanders won caucuses Saturday in three western states and never contacted the senator’s camp to congratulate him, according to the report.

A Clinton spokeswoman declined to comment to Politico and a Sanders strategist told the publication that he didn’t intend to be disrespectful.

“He’s very happy to do the right thing, whatever the right thing happens to be,” Tad Devine said. “We just have to take into account the logistics and the time zones. I’m sure when you have the Wisconsin primary, if he loses it, he’s going to call and congratulate her. He’s not trying to be ungracious at all.”