1 verse has
doubts
in Edition Clear Qur'an by Talal Itani / Al-Maaida (The Table)

5:106O you who believe! When death approaches one of you, let two reliable persons from among you act as witnesses to the making of a bequest, or two persons from another people if you are travelling in the land and the event of death approaches you. Engage them after the prayer. If you have doubts, let them swear by God: “We will not sell our testimony for any price, even if he was a near relative, and we will not conceal God’s testimony, for then we would be sinners.”