We are using Google Pay in our app with latest play-services-wallet:18.0.0 One of the users reported issues after upgrade to Android 11 on Pixel 2.
Since I don't have this devices, I have tried to recreate this issue on emulator with Google Play.
Calling AutoResolveHelper.resolveTask(paymentsClient.loadPaymentData(request), activity, GOOGLE_PAYMENT_REQUEST_CODE)
results in following dialog:

onActivityResult will then provide intent with Status class with code 409 - aborted
Emulator with Android 10 and Android 9 is working just fine.
Any idea what might be wrong?
Edit: Logcat from user:
09-11 17:06:13.547 8927 16994 E TapAndPay: Unable retrieve off body sensor. Sensor is null. [CONTEXT service_id=79 ]
09-11 17:06:13.550 8836 9848 W TapAndPayUtils: Failed to retrieve in app payment credential! status = 13 message = Storage key missing
09-11 17:06:13.528 8927 16994 E TapAndPay: Unable retrieve off body sensor. Sensor is null. [CONTEXT service_id=79 ]
09-11 17:06:13.531 8927 16994 E AsyncOperation: serviceID=79, operation=RetrieveInAppPaymentCredential [CONTEXT service_id=259 ]
09-11 17:06:13.531 8927 16994 E AsyncOperation: OperationException[Status{statusCode=Storage key missing, resolution=null}]
09-11 17:06:13.531 8927 16994 E AsyncOperation: at atri.b(:com.google.android.gms@203315046@20.33.15 (150400-330018294):24)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at atse.a(:com.google.android.gms@203315046@20.33.15 (150400-330018294):3)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at yof.run(:com.google.android.gms@203315046@20.33.15 (150400-330018294):11)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at blzm.run(:com.google.android.gms@203315046@20.33.15 (150400-330018294):2)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at qzr.b(:com.google.android.gms@203315046@20.33.15 (150400-330018294):12)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at qzr.run(:com.google.android.gms@203315046@20.33.15 (150400-330018294):7)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at rfq.run(:com.google.android.gms@203315046@20.33.15 (150400-330018294):0)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at java.lang.Thread.run(Thread.java:923)
09-11 17:06:13.531 8927 16994 E AsyncOperation: Caused by: atpe: No storage key available
09-11 17:06:13.531 8927 16994 E AsyncOperation: at atpk.a(:com.google.android.gms@203315046@20.33.15 (150400-330018294):9)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at atkt.a(:com.google.android.gms@203315046@20.33.15 (150400-330018294):81)
09-11 17:06:13.531 8927 16994 E AsyncOperation: at atri.b(:com.google.android.gms@203315046@20.33.15 (150400-330018294):10)
09-11 17:06:13.531 8927 16994 E AsyncOperation: ... 9 more