I keep getting the message this copy of the install macOS Big Sur application is damaged and can’t be used to installed macOS. I get the same message with Monterey. I have MacBook Air early 2015 even though I bought it in 2017

I have the MacBook Air early 2015. My operating system doesn’t flip over to upgrade. I get the message this copy of the install macOS, Monterey or Big Sur application is damaged and can’t be used to install macOS. This happened last year and I know because TurboTax required an upgrade to my operating system so I actually was on the phone with Apple support and it took a very very long time but it upgraded and I was able to go to Catalina but now I’m stuck again