# gfps_handle_char_kbp: failed, result 3

<span style="color: rgb(255,0,0);">**Q:**</span>GFPS 配对失败，log提示：

gfps_handle_char_kbp: failed, result 3(GFPS_WRITE_RESULT_ERROR_MESSAGE_TYPE) or

    gfps_handle_char_kbp: failed, decrypt_result 3(GFPS_WRITE_RESULT_ERROR_MESSAGE_TYPE) 

<span style="color: rgb(255,0,0);">**A:**</span>解密出来的kbp(key based pairing request )不正确，原因是model id和public key,private key不匹配，导致解密kbp时使用的aes key不正确。

请确认MCU cfg tool中填写的model id和public key,private key是不是匹配的

另外需要注意：

![](images/gfps_handle_char_kbp_+failed,+result+3_eddd7671.jpg)

model id的注册请参考wiki：[model_id 注册](/pages/viewpage.action?pageId=157379126)

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