Device not send the join uplink when change the keys from OTAA to ABP

[AA.21]

Hi,

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I have used Stm8 controller and I have change the keys from OTAA to ABP. In OTAA mode I have get the joining uplink(first uplink) but i didn't get the joining uplink in ABP.​ When I reset the device after get the second uplink in the network server. At that time I have got the first uplink in the network server. What is the reason.

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Second one is, I got the first uplink when reset the device after got the second uplink. as like this again'i reset the device before get second uplink,that time the network server did not get the joining uplink(first uplink).

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I have used TTN server and STM8 Controller.

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