Connect to the Network-Server postgresql database
DELETE FROM device_activation where E'\\x<REPLACE_ME_DEV_EUI>'=dev_eui;
this should delete all accepted/generated JOINs (also the current one) for the device
USE THIS AS A LAST RESORT AND AT YOUR OWN RISK
@chopmann, I agree that adding this as an option would be a good idea. Please feel free to create a GitHub issue for this. Currently I’m working on some refactoring and cleanup of the code (not yet public) which is the reason why I’m pushing back on adding new features at this moment. With a GitHub issue it stays on the list 
I have added this feature for testing purpose with the help of OFFSET in Network Server and created REST API in the Application server
DELETE FROM device_activation WHERE id IN (SELECT id from device_activation WHERE dev_eui = <DEV_EUI> ORDER BY id DESC OFFSET 20)
if you would like to contribute to this feature then I can submit PR for this feature…
Thanks
Please check the below screenshot of UI par of clear dev-nonce. Can you please review I’m waiting for your suggestion…
This confirmation again alerts you when you click on the YES button for double confirmation…
It looks superb! 
If you upload the code, I can do spell checking.
Maybe using the same Icons as “Delete” (for example when you delete an application) and the color would make it consistent with the rest. I’d put the button on the Activation Tab, that way you can reuse the Trash-bin icon.
The delete button uses an “alert”, I like the way you did it, is just different then the rest.
@chopmann @brocaar
I will put the clear dev-nonce button on Activation Tab but it will show if the device is activated or not…
I have make PR for chirpstack-api for Network Server and Application Server changes I will make PR for other changes once API is approved and merged.
Hello,
I have same problem with Axioma E3, thia are restarting after about 32 Uplink messages or about 7 days,
after restart Device try to Join with same dev_nonce.
Can you please give instructions to install in ChirpStack the action button to clear old dev_nonce ?,
I have tested to select rows from PostgreSQL regarding specific devEUI and sort by date created,
I think all record can be deleted and left only last one which is activ.
SELECT * FROM device_activation WHERE id IN (SELECT id from device_activation WHERE dev_eui = ‘devEUI that you want’ ORDER BY id DESC) ORDER BY created_at DESC;
This give output sorted by time created.
Will be very nice to have this code run automatically just using chek button.
Thanks for UI help.
Finally last SQL command
DELETE FROM device_activation WHERE id IN (SELECT id from device_activation WHERE dev_eui = ‘devEUI that you want’ ORDER BY id DESC OFFSET 2);
This will leave 2 last records, since the rejoin start from zero to 41, this will delete older record of dev_nonce.
How can I insert button with this command in UI ?
Thanks
Is not yet released. Please be patient. @brocaar is working on a refactor, that is probably 
going to make contributing easier.
Is it possible to run this delete via an pgAdmin console? I’m struggling with the bytea types.
I have around 5 inaccesible nodes with this issue and being able to run your update would be a life saver.
Thanks
Hello guys,
I’m facing the same problem “Validate dev-nonce error”.
I already cleared the device from device_activation table on database. But still join request after join request. Can you help please?
The best way is to do this using the web-interface. Have you tried that?
Hello brocaar, thanks for your help
No ideia how to do it using web-interface.
Can you give some tips please?
Hi @NULL1
clear dev-nonce button on Activation Tab
Go to device details page → Go to Activation Tab → Clear DevNonce Button
Is there a way to read the last dev nonce value for selected device? Preferably from postgres console without pgAdmin (database accessible from localhost only)?
Reason is that I had two devices out of gateway’s reach for almost a month, so I would like to check how the devices firmware handled that situation.
Never noticed there is a button to do that 
Thank you
Ok, found it:
# Connect to postgre terminal:
sudo -u postgres psql
In postgre terminal:
-- Connect to network server database (v3):
\c chirpstack_ns
-- List records for DevEUI = 0123456789abcdef:
SELECT * FROM device_activation WHERE id IN (SELECT id from device_activation WHERE dev_eui = '\x0123456789abcdef' ORDER BY id DESC) ORDER BY created_at DESC;
-- Or list all records:
SELECT * FROM device_activation ORDER BY created_at DESC;
-- Quit postgres:
\q