receiving indication information of a first transmission resource to be used by the first terminal to send data on a sidelink from an access network device, wherein the sidelink is a wireless communication link between the first terminal and a second terminal, and wherein the first transmission resource is a resource of an unlicensed spectrum;

performing a channel access procedure on the unlicensed spectrum;

determining that a failure occurs in the channel access procedure performed on the unlicensed spectrum by determining that a quantity of times that the failure occurs in the channel access procedure on a channel of one or more channels associated with the unlicensed spectrum is greater than a first threshold; and

sending first information to the access network device when the failure occurs in the channel access procedure performed on the unlicensed spectrum, wherein the first information comprises information about the channel on which the failure occurs in the channel access procedure, wherein after receiving the first information, the access network device determines, based on content of the first information, the unlicensed spectrum on which the failure occurs in the channel access procedure.