Why was Narayani Sena punished in the Mahabharata War? What wrong did they do on their part which caused their end?

Why was Narayani Sena punished in the Mahabharata War? What wrong did they do on their part which caused their end? Army of Indraprasth was personally trained by Arjuna with great commitment. That army became a part of world conquest for Rajasuya sacrifice. Then dice game happened where Duryodhana won Indraprasth and sent Pandavas on exile. After thirteen years Duryodhana’s obstinacy and foolishness paved way to Kurukshetra war. Indraprasth army which was loyal to Pandavas have to fight against them and die for no fault of them. Coming to Narayani Sena,it was the decision of Narayana himself to make them fight against him and get killed mostly by Arjuna. One akshouhini Narayani Sena along with Kritavarma’s one akshouhini army fought for Kauravas. Krishna willed it and let it happen because the purpose of his incarnation itself is to relieve the burden of the earth. Ultimately Narayan himself drove the chariot to get his Narayani Sena killed by Parth. In Sanjaya’s words There were those who were reared in Gokula. They were extremely well versed in fighting. Many thousands of them arrayed themselves as masses of samshaptakas. All of them approached Partha and went to Vaivasvata’s eternal abode.22 Ch 4 Karna parva Bori critical Edition Like soldiers of Indraprasth fought against Pandavas,Narayani Sena fought against Krishna . Soldiers in those times didn’t have the free will to fight for whomever they chose. Purpose for Kurukshetra war was different though looked like a dispute between cousins for kingdom. It was the divine plan initiated by Trinity ,Indra and other gods to relieve the burden of earth. So Narayani Sena fighting against Krishna can’t be taken as punishment. My answer is based on story of Vyasa Bharat