Just tested here on and Wemos D1 Mini with the single exception that I removed the 'mqtt_client_id' and got the below result.
The MQTT result when viewed in a simple Node-Red sketch is also number perfect.
Maybe your MQTT server/broker is at fault.
Setting up....
Connecting to XXXXX.....OK
IP address: 192.168.1.26
Configuring OTA device...OK
Configuring MQTT server...
Server IP: 192.168.0.101
Username: XXXXX
MQTT configured!
Setup complete. Running loop...
Attempting MQTT connection...connected
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