I have created a small script. After some trying I cannot find where my mistake is... I keep getting error no path found (creep.moveto() returns -2). Here is my code:

var roleHarvester = {

/** @param {Creep} creep **/
run: function(creep) {
    if(creep.carry.energy < creep.carryCapacity) {
        
        var source = creep.room.find(FIND_SOURCES)[1];
        
        if(creep.harvest(source) == ERR_NOT_IN_RANGE) {
            console.log('x: ' + source.pos.x);
            console.log('y: ' + source.pos.y);
            
            if (creep.moveTo(source) == -2) {
                console.log('Cannot find path');
            }
        }
    }
    else {
        if(creep.transfer(Game.spawns['Spawn1'], RESOURCE_ENERGY) == ERR_NOT_IN_RANGE) {
            creep.moveTo(Game.spawns['Spawn1']);
        }
    }
}
};

module.exports = roleHarvester;

It shows in the log:

x: 11
y: 30
Cannot find path

The x and y value are the correct values of the source.

Why can't it find it's path?

I am just new to this game and I have created a very simple move script. I know it isn't efficient at all but my harvester just doesn't move. What do I have to do to solve this problem? It doesn't give any errors

I have created this creep with the following commandline:

Game.spawns['Spawn1'].spawnCreep([MOVE, WORK, CARRY], 'Harvester')

Main:

var roleHarvester = require('role.harvester');
var roleDefender = require('role.defender');
var roleBuilder = require('role.builder')

module.exports.loop = function () {

var amountOfCreeps = 0;
for(var name in Game.creeps) {
    
    if (name.name == 'Builder') {
        var creep = Game.creeps[name];
        roleBuilder.run(creep);
    }
    else if (name.name == 'Harvester') {
        var creep = Game.creeps[name];
        roleHarvester.run(creep);
    }
    else if (name.name == 'Defender') {
        var creep = Game.creeps[name];
        roleDefender.run(creep);
    }
    
    amountOfCreeps++;
}
}

role.builder:

var roleBuilder = {

/** @param {Creep} creep **/
run: function(creep) {
    if (creep.carry.energy === 0) {
        if (creep.withdraw(Game.spawns['Spawn1'], RESOURCE_ENERGY) == ERR_NOT_IN_RANGE) {
            creep.moveTo(Game.spawns['Spawn1']);
        }
    }
    else {
        var sources = creep.room.find(FIND_STRUCTURES);
        if (creep.build(sources[0]) == ERR_NOT_IN_RANGE) {
            creep.moveTo(sources[0]);
        }
    }
}
};

module.exports = roleBuilder;

role.defender (not yet edited to my liking):

var roleDefender = {

/** @param {Creep} creep **/
run: function(creep) {
    if(creep.carry.energy < creep.carryCapacity) {
        var sources = creep.room.find(FIND_SOURCES);
        if(creep.harvest(sources[0]) == ERR_NOT_IN_RANGE) {
            creep.moveTo(sources[0]);
        }
    }
    else {
        if(creep.transfer(Game.spawns['Spawn1'], RESOURCE_ENERGY) == ERR_NOT_IN_RANGE) {
            creep.moveTo(Game.spawns['Spawn1']);
        }
    }
}
};

module.exports = roleDefender;

role.harvester:

var roleHarvester = {

/** @param {Creep} creep **/
run: function(creep) {
    if(creep.carry.energy < creep.carryCapacity) {
        var sources = creep.room.find(FIND_SOURCES);
        if(creep.harvest(sources[0]) == ERR_NOT_IN_RANGE) {
            creep.moveTo(sources[0]);
        }
    }
    else {
        if(creep.transfer(Game.spawns['Spawn1'], RESOURCE_ENERGY) == ERR_NOT_IN_RANGE) {
            creep.moveTo(Game.spawns['Spawn1']);
        }
    }
}
};