Resource never released

Hello. I'm currently using this library to connect to an amazon STS Endpoint
This endpoint changes every 15 minutes and I have to change it whenever I encounter a connection failure. If I try to connect to a non valid endpoint, the application throws this error

`MqttException (0) - java.io.IOException: WebSocket Response header: Incorrect upgrade.
at org.eclipse.paho.client.mqttv3.internal.ExceptionHelper.createMqttException(ExceptionHelper.java:38)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:715)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:422)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:152)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:265)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.io.IOException: WebSocket Response header: Incorrect upgrade.
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketHandshake.receiveHandshakeResponse(WebSocketHandshake.java:148)
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketHandshake.execute(WebSocketHandshake.java:76)
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketSecureNetworkModule.start(WebSocketSecureNetworkModule.java:63)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:701)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:422) 
at java.util.concurrent.FutureTask.run(FutureTask.java:237) 
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:152) 
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:265) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 
at java.lang.Thread.run(Thread.java:818) 
`

The real problem comes when I update the connection parameters with a new STS endpoint and try to connect to the new one. In this case the error I'm getting is this one

`E/StrictMode: A resource was acquired at attached stack trace but never released. See java.io.Closeable for information on avoiding resource leaks.
java.lang.Throwable: Explicit termination method 'close' not called
at dalvik.system.CloseGuard.open(CloseGuard.java:184)
at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:287)
at org.eclipse.paho.client.mqttv3.internal.SSLNetworkModule.start(SSLNetworkModule.java:108)
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketSecureNetworkModule.start(WebSocketSecureNetworkModule.java:61)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:701)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:422)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:152)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:265)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)`

And not only trying to reconnect but also, every time I send a message to the publish topic.
It works fine at the start, but after a day or two, it closes the connection and it can never reopen it

I've tried to update to the version 1.2.1 but it only works in devices with android 7.0 or superior.
¿Can you help me?
- [ X] Bug exists Release Version 1.2.0 ( Master Branch)
- [? ] Bug exists in MQTTv3 Client on Snapshot Version 1.2.1-SNAPSHOT (Develop Branch)
- [ ?] Bug exists in MQTTv5 Client on Snapshot Version 1.2.1-SNAPSHOT (Develop Branch)