| Error message | Parallel session detected | 
|---|---|
| Description | The payment failed due to another session being open for the user. | 
| Categories | Pay-in  | 
Causes
Another hosted session is detected for the same user and hasn’t yet been completed.What to do
Check for a duplicated transaction request for the same user. The payment session is ended when either of the following occur:- The 
ProcessingStatusproperty is returned with the valuePENDING_SUCCEEDED, indicating a successful session. - The 
Statuschanges toFAILED, indicating an unsuccessful one.