Hi... these are the few things that I tried.

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1. Delete old 0.9.14. with account intact
2. Install old 0.9.15
3. Start Application.
=> Exception. (as described a few posts back with stack trace)

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1. Delete Wazapp account
2. Start Application 0.9.15
3. Register and Verify. Wazapp says successful registration and asks to restart app.
4. Start Application.
=> Same exception as above

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1. Delete Wazapp account. Delete 0.9.15.
2. Reboot Phone
3. Install 0.9.15
4. Start Application 0.9.15
5. Register and Verify. Wazapp says successful registration and asks to restart app.
6. Start Application.
=> Same exception as above

Thank you.