“...they go forth to the kings of the entire inhabited earth, to gather them together to the war of the great day of God the Almighty.”
Revelation 16:14

Question:
“How can the world rulers call for God’s help when Revelation describes them as gathering to fight Him at Armageddon?”
The call from the superior authorities prior to the Divine Rescue is not to be confused with the evil assembly of the kings of the earth at Armageddon.
In our day, the world rulers - the kings of the earth and their governments - hold the authority which rightfully belongs to the Heavens. For this reason, only they can offer it to subject it to God’s authority, therefore only they can call for God’s rescue.
When the rescue begins, some — who feel that they had been given their positions by Heaven — will feel that their work is over. The will leave high office, and delightedly follow the gentle way of Life as an ordinary soul. Others will remain for a while, eager to do the very best they can for the population under their care, and will follow their peers at a later time.
Revolt
Armageddon takes place later, sometime after the call for help, sometime during Christ’s reign. At this time, the remaining rulers will be those for whom power is addictive, who want to retain their past unsupervised authority. These are the ones for whom Revelation is a warning, the ones who will actually fight against Heavens authority in order to retrieve independence.
This prophesied approach to the Heavens by these rulers, whom Revelation calls the “kings of the earth”, is the very antithesis of the superior authorities’ approach to the Heavens in our day. So whereas the Last Prophet induces Mankind to call to God for help, the very different false prophet of Revelation induces the rulers of it’s particular time during Christ’s reign to fight against Heaven.
These two instances - one beneficial and one treasonous - are not to be confused. However, it is an indication that God’s kind rescue will be discarded as past history - even by some of those high offices who were privileged to call to Him - when they want to pursue their own aims.