Method for operating an ultrasonic flowmeter , wherein the ultrasonic flowmeter has at least one first ultrasonic transducer , wherein the first ultrasonic transducer is designed as a transmitting unit and as a receiving unit, and a measuring tube , wherein a medium flows through the measuring tube during operation, and a control and evaluation unit for controlling at least the first ultrasonic transducer and for determining the flow velocity or the flow rate of the medium, wherein the method comprises the following steps: - capturing at least one first ringing signal of the first ultrasonic transducer and detecting a first ringing debugging signal based on the at least one captured first ringing signal, - emitting a first measurement signal into the medium through the first ultrasonic transducer , wherein a first ringing measurement signal is generated in the first ultrasonic transducer , - receiving a measurement signal as a first received signal by the first ultrasonic transducer , wherein the first received signal and the first ringing measurement signal are superimposed to form a first superimposed signal , - determining a first correction signal by subtracting the first ringing debugging signal from the first superposition signal , and - determining the flow velocity or flow rate based on the first correction signal . wherein the ultrasonic flowmeter has at least one first ultrasonic transducer , wherein the first ultrasonic transducer is designed as a transmitting unit and as a receiving unit, and a measuring tube , wherein a medium flows through the measuring tube during operation, and a control and evaluation unit for controlling at least the first ultrasonic transducer and for determining the flow velocity or the flow rate of the medium, wherein the method comprises the following steps: - capturing at least one first ringing signal of the first ultrasonic transducer and detecting a first ringing debugging signal based on the at least one captured first ringing signal, - emitting a first measurement signal into the medium through the first ultrasonic transducer , wherein a first ringing measurement signal is generated in the first ultrasonic transducer , - receiving a measurement signal as a first received signal by the first ultrasonic transducer , wherein the first received signal and the first ringing measurement signal are superimposed to form a first superimposed signal , - determining a first correction signal by subtracting the first ringing debugging signal from the first superposition signal , and - determining the flow velocity or flow rate based on the first correction signal . - capturing at least one first ringing signal of the first ultrasonic transducer and detecting a first ringing debugging signal based on the at least one captured first ringing signal, - emitting a first measurement signal into the medium through the first ultrasonic transducer , wherein a first ringing measurement signal is generated in the first ultrasonic transducer , - receiving a measurement signal as a first received signal by the first ultrasonic transducer , wherein the first received signal and the first ringing measurement signal are superimposed to form a first superimposed signal , - determining a first correction signal by subtracting the first ringing debugging signal from the first superposition signal , and - determining the flow velocity or flow rate based on the first correction signal . <EOS>