Sens. Amy Klobuchar (D-Minn.) and Mike Lee (R-Utah) are questioning whether Google tried to influence one of its critics to change his testimony before a hearing last week on dominant app stores.

Jared Sine, chief legal officer at Match Group, testified during the hearing that a Google employee had called his company the night before and asked “why our testimony was different than what we’d said about the situation in our earnings call earlier this year.”

In a letter to Google’s senior director of government affairs and public policy, Wilson White, the top two senators on the panel that held the hearing said they “are deeply troubled by the possibility that Google may have attempted to influence another witness’s testimony.”