If you have some trouble entering Sangha app – make sure you have the app’s latest version in the store of your smartphone. In case you will need to recover your account – you can watch this video how it works.
If there is still a problem – and you are using an iPhone – you can write “sangha://reset” into your phone’s internet browser and click enter. That way you will reset the app and you can login with the same account you were using 😉