Bug since 1.12

Since 1.12, after player leaves and rejoins, tools no longer work. The following error is shown: ```Tried to equip Item Diamond Pickaxe (278:1)x1 tags:CgAACQQAZW5jaAoBAAAAAgIAaWQPAAIDAGx2bAQAAAA= but have Item Unknown (278:35)x1 tags:CgAACQQAZW5jaAoBAAAAAgIAaWQPAAIDAGx2bAQAAAA= in target slot```

Only happens when using this plugin