This sounds like you have a starter solenoid that is failing. Basically the solenoid finds a spot in the windings where it is not able to complete the circuit and it clicks one time but does not turn the starter gear.
You can take a small hammer and tap on the starter solenoid and this will actually cause it to move slightly and it is normally enough to get it to turn over. However, as soon as it finds another worn spot then it will do this again.
I would just replace the starter.
Please see the process below and let us know if you have other questions.
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Thursday, August 5th, 2021 AT 4:22 PM