See the error below:
[12:56:36 WARN]: [luckperms-1] WARN me.lucko.luckperms.lib.hikari.pool.PoolBase

• luckperms-hikari - Failed to validate connection me.lucko.luckperms.lib.mysql.
  jdbc.JDBC4Connection@199839a (No operations allowed after connection closed.). P
  ossibly consider using a shorter maxLifetime value.
  [12:56:36 WARN]: java.sql.SQLTransientConnectionException: luckperms-hikari - Co
  nnection is not available, request timed out after 7878ms.
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.pool.HikariPool.createT
  imeoutException(HikariPool.java:676)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.pool.HikariPool.getConn
  ection(HikariPool.java:190)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.pool.HikariPool.getConn
  ection(HikariPool.java:155)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.HikariDataSource.getCon
  nection(HikariDataSource.java:100)
  [12:56:36 WARN]: at me.lucko.luckperms.common.storage.implementation.sql.
  connection.hikari.HikariConnectionFactory.getConnection(HikariConnectionFactory.
  java:127)
  [12:56:36 WARN]: at me.lucko.luckperms.common.messaging.sql.SqlMessenger.
  getConnection(SqlMessenger.java:84)
  [12:56:36 WARN]: at me.lucko.luckperms.common.messaging.sql.AbstractSqlMe
  ssenger.pollMessages(AbstractSqlMessenger.java:84)
  [12:56:36 WARN]: at me.lucko.luckperms.common.plugin.scheduler.AbstractJa
  vaScheduler$WrappedRunnable.run(AbstractJavaScheduler.java:79)
  [12:56:36 WARN]: at java.util.concurrent.Executors$RunnableAdapter.call(U
  nknown Source)
  [12:56:36 WARN]: at java.util.concurrent.FutureTask.runAndReset(Unknown S
  ource)
  [12:56:36 WARN]: at java.util.concurrent.ScheduledThreadPoolExecutor$Sche
  duledFutureTask.access$301(Unknown Source)
  [12:56:36 WARN]: at java.util.concurrent.ScheduledThreadPoolExecutor$Sche
  duledFutureTask.run(Unknown Source)
  [12:56:36 WARN]: at java.util.concurrent.ThreadPoolExecutor.runWorker(Unk
  nown Source)
  [12:56:36 WARN]: at java.util.concurrent.ThreadPoolExecutor$Worker.run(Un
  known Source)
  [12:56:36 WARN]: at java.lang.Thread.run(Unknown Source)
  [12:56:36 WARN]: Caused by: me.lucko.luckperms.lib.mysql.jdbc.exceptions.jdbc4.M
  ySQLNonTransientConnectionException: No operations allowed after connection clos
  ed.
  [12:56:36 WARN]: at sun.reflect.NativeConstructorAccessorImpl.newInstance
  0(Native Method)
  [12:56:36 WARN]: at sun.reflect.NativeConstructorAccessorImpl.newInstance
  (Unknown Source)
  [12:56:36 WARN]: at sun.reflect.DelegatingConstructorAccessorImpl.newInst
  ance(Unknown Source)
  [12:56:36 WARN]: at java.lang.reflect.Constructor.newInstance(Unknown Sou
  rce)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.Util.handleNewInsta
  nce(Util.java:425)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.Util.getInstance(Ut
  il.java:408)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.SQLError.createSQLE
  xception(SQLError.java:919)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.SQLError.createSQLE
  xception(SQLError.java:898)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.SQLError.createSQLE
  xception(SQLError.java:887)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.SQLError.createSQLE
  xception(SQLError.java:861)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.ConnectionImpl.thro
  wConnectionClosedException(ConnectionImpl.java:1192)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.ConnectionImpl.chec
  kClosed(ConnectionImpl.java:1187)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.mysql.jdbc.ConnectionImpl.setN
  etworkTimeout(ConnectionImpl.java:5494)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.pool.PoolBase.setNetwor
  kTimeout(PoolBase.java:550)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.pool.PoolBase.isConnect
  ionAlive(PoolBase.java:165)
  [12:56:36 WARN]: at me.lucko.luckperms.lib.hikari.pool.HikariPool.getConn
  ection(HikariPool.java:179)
  [12:56:36 WARN]: ... 13 more
  [12:56:47 INFO]: zAlyson lost connection: ºcVocÛ demorou muito para autenticar-s
  e como um staffer.
  [12:56:48 WARN]: handleDisconnection() called twice

~

Check the storage system errors page on the wiki next time.