BungeeTabList Error

14:11:12 [WARNING] [BungeeTabListPlus] Unable to load Config
14:11:12 [WARNING] [BungeeTabListPlus] null
Cannot create property=sendPing for JavaBean=codecrafter47.bungeetablistplus.config.MainConfig@36ac8a63
 in 'reader', line 4, column 1:
    updateOnPlayerJoinLeave: true
    ^
Unable to find property 'sendPing' on class: codecrafter47.bungeetablistplus.config.MainConfig
 in 'reader', line 9, column 11:
    sendPing: true
              ^

    at org.yaml.snakeyaml.constructor.Constructor$ConstructMapping.constructJavaBean2ndStep(Constructor.java:307)
    at org.yaml.snakeyaml.constructor.Constructor$ConstructMapping.construct(Constructor.java:189)
    at org.yaml.snakeyaml.constructor.Constructor$ConstructYamlObject.construct(Constructor.java:340)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructObject(BaseConstructor.java:182)
    at codecrafter47.bungeetablistplus.yamlconfig.YamlConfig$MyConstructor.constructObject(YamlConfig.java:218)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructDocument(BaseConstructor.java:141)
    at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:127)
    at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:481)
    at org.yaml.snakeyaml.Yaml.loadAs(Yaml.java:441)
    at codecrafter47.bungeetablistplus.yamlconfig.YamlConfig.read(YamlConfig.java:79)
    at codecrafter47.bungeetablistplus.yamlconfig.YamlConfig.read(YamlConfig.java:75)
    at codecrafter47.bungeetablistplus.BungeeTabListPlus.onEnable(BungeeTabListPlus.java:217)
    at codecrafter47.bungeetablistplus.BungeePlugin.onEnable(BungeePlugin.java:40)
    at net.md_5.bungee.api.plugin.PluginManager.enablePlugins(PluginManager.java:227)
    at net.md_5.bungee.BungeeCord.start(BungeeCord.java:267)
    at net.md_5.bungee.BungeeCordLauncher.main(BungeeCordLauncher.java:55)
    at net.md_5.bungee.Bootstrap.main(Bootstrap.java:15)
Caused by: org.yaml.snakeyaml.error.YAMLException: Unable to find property 'sendPing' on class: codecrafter47.bungeetablistplus.config.MainConfig
    at org.yaml.snakeyaml.introspector.PropertyUtils.getProperty(PropertyUtils.java:132)
    at org.yaml.snakeyaml.introspector.PropertyUtils.getProperty(PropertyUtils.java:121)
    at org.yaml.snakeyaml.constructor.Constructor$ConstructMapping.getProperty(Constructor.java:317)
    at org.yaml.snakeyaml.constructor.Constructor$ConstructMapping.constructJavaBean2ndStep(Constructor.java:240)
    ... 16 more
14:11:12 [WARNING] [BungeeTabListPlus] Disabling Plugin