Connection error with LYWSD03MMC

[buphon]

Hello!
I am trying to flash a LYWSD03MMC thermometer with the Telink Flasher tool.
The device appears ready to pair, in fact, it shows temperature and humidity in Telink Flasher, but it appears as disconnected, and I can't do activation.
This is the first time this has happened to me, as I have succeeded in other instances with other thermometers.
The error I get is the following:

17:46:18: Searching for devices
17:46:21: Connecting to: LYWSD03MMC
17:46:23: Hardware Revision String: B1.5
17:46:23: Software Revision String: 0159
17:46:23: Firmware Revision String: 2.1.1_0159
17:46:23: Detected Mi device
17:46:23: NotSupportedError: GATT operation failed for unknown reason.
17:46:23: Reconnect 1 from 5
17:46:23: Detected Mi device
17:46:23: TypeError: Cannot read properties of null (reading 'substr')
17:46:23: Reconnect 2 from 5
17:46:23: Detected Mi device
17:46:23: TypeError: Cannot read properties of null (reading 'substr')
17:46:23: Reconnect 3 from 5
17:46:23: Detected Mi device
17:46:23: TypeError: Cannot read properties of null (reading 'substr')
17:46:23: Reconnect 4 from 5
17:46:23: Detected Mi device
17:46:23: TypeError: Cannot read properties of null (reading 'substr')
17:46:23: Reconnect 5 from 5
17:46:23: Detected Mi device
17:46:23: TypeError: Cannot read properties of null (reading 'substr')
17:46:23: Something went wrong, too many reconnects

I appreciate any help. Best regards.

[pvvx]

What does MiHome show with this thermometer?

[buphon]

Hi
In Xiaomi home app shows temperature, humidity and battery levels, with a warning of bt gateway not connected.

I've tried another mobile phone, and now the device is connected, but Do activation button is missed.

17:10:21: Searching for devices
17:10:41: Get Advertising MAC (Web Experimental Features!)
17:10:41: TypeError: device.watchAdvertisements is not a function
17:10:41: Reconnect 1 from 5
17:10:45: Hardware Revision String: B1.5
17:10:45: Software Revision String: 0159
17:10:45: Firmware Revision String: 2.1.1_0159
17:10:45: Detected Mi device
17:10:46: NotSupportedError: GATT operation failed for unknown reason.
17:10:46: Reconnect 2 from 5
17:10:46: Detected Mi device
17:10:46: TypeError: Cannot read properties of null (reading 'substr')
17:10:46: Reconnect 3 from 5
17:10:46: Software Revision String: 0159
17:10:46: Detected Mi device
17:10:46: TypeError: Cannot read properties of null (reading 'substr')
17:10:46: Reconnect 4 from 5
17:10:46: Hardware Revision String: B1.5
17:10:46: Software Revision String: 0159
17:10:46: Firmware Revision String: 2.1.1_0159
17:10:46: Detected Mi device
17:10:46: Connected

The same from Windows... Button missed.

17:20:01: Searching for devices
17:20:36: Get Advertising MAC (Web Experimental Features!)
17:20:36: Connecting to: LYWSD03MMC
17:20:37: MiVer5, DevID: 0x055B-LYWSD03MMC, FnCnt: 5, CtrID: 0x5858 Not bound, Standard certification, MAC: A4C138C27748, Data encrypted
17:20:47: Hardware Revision String: B1.5
17:20:47: Software Revision String: 0159
17:20:47: Firmware Revision String: 2.1.1_0159
17:20:47: Detected Mi device
17:20:47: Connected

[pvvx]

README

Warning: Firmware LYWSD03MMC version 2.1.1_0159 requires registration in MI-Home and obtaining IDs.