Sometimes it can happen that blocks can not be set in the game. In order to determine the exact cause, the following points should be considered:
Wrong server settings
A default active feature of Minecraft servers is the spawn-protection. This prevents players from destroying the spawn point. However, this should be controlled by corresponding plugins like WorldGuard and can therefore be deactivated. Go to the server.properties file in your server folder. Set the value spawn-protection to 0.
Region is set incorrectly
Some Mine-Home plugins use regions to define the playable area. Whether a plugin uses this, is mentioned in the plugin description. If these regions are set incorrectly, this may interfere with the entire gameplay. Make sure to set the positions so that they contain the entire playing area. The following figure illustrates the setting of the positions:
Is the Mine-Home plugin the cause?
To answer this question you should write down the coordinates during the game, where you can not set a block. Now you end the game and teleport to the coordinates and try to set a block. If it now works, you can confirm an error at the Mine-Home plugin. If it still does not work, another plugin is the cause.