jwt.isExpired() throws "TypeError: Cannot read property 'exp' of undefined"

[nebosite]

I'm hitting a weird problem trying to call the isExpired function on a Jwt.

Setup: Single-page web app is sending access token to a server. Server is verifying the token.

Packages: "@okta/jwt-verifier": "^2.1.0", "@okta/oidc-middleware": "^4.1.0",

Server code:

    import OktaJwtVerifier from '@okta/jwt-verifier';
    const oktaJwtVerifier:OktaJwtVerifier = new OktaJwtVerifier(oktaConfig);
...
    const jwt = await oktaJwtVerifier.verifyAccessToken(token, audience) 
    console.log(`JWT:  ${JSON.stringify(jwt)}`)
    console.log(`IsExpired:  ${jwt.isExpired()}`)

Output:

JWT:  {"header":{"typ":"JWT","alg":"RS256","kid":"[...]"},"claims":{"ver":1,"jti":"[...]","iss":"[internal uri]","aud":"api://default","iat":1623249209,"exp":1623252809,"cid":"0oa1j3h0l6b5DdVTm1d8","uid":"00u1g2d7eprtOZQrC1d8","scp":["email","profile","openid"],"sub":"me","mail":"[email protected]"}}
ERROR:  TypeError: Cannot read property 'exp' of undefined {}

Expected: instead of an error, should see "isExpired: false"

Side question: What happens when I try to verify an expired token? Will verifyAccessToken throw? Do I even need to check the expiration?