NHTSA Complaint #11716126 — 2021 CHEVROLET TAHOE

2021 tahoe with 3.0L diesel engine and 139k miles recently began overheating when on interstate but temp would jump up quickly then quickly back down. Reduced acceleration mode is triggered and AC is turned off automatically. Diagnostic report shows coolant control valve error code and it was explained to me that valve is sticking then as engine pressure rises, it knocks it loose again explaining the quickly jumps and dips in temp. Fan runs constantly from moment it is started too. When looking for the part online to get an idea of repair cost, there was a bulletin about this being a known issue in the 2021 tahoes with the diesel engines and bulletin states GM extended special coverage for 15yrs/150k miles. When I called dealer to schedule service, I was told this bulletin doesnt come up under my vin number despite it having the same issues, error codes, year, make, model, and engine.