Logack is not deleting the files when I set maxHistory

This is how my xml file looks like, while I was running my test to check whether the log files were deleted. every minute and keeping only 2 files , but files just keep being created but not deleted as it was defined.

<appender name="FOLD_LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<File>/app/fold/logs/out.log</File>

<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!-- rollover daily -->
<fileNamePattern>/app/fold/logs/out_%d

{yyyy-MM-dd_HH-mm}

.txt</fileNamePattern>

<maxHistory>2</maxHistory>
</rollingPolicy>

<encoder>
<pattern>%d

{yyyy-MMM-dd HH:mm:ss.SSS}

[%thread] %-5level %logger

{36}

----- %msg%n</pattern>
</encoder>

</appender>