Wulfsten's Challenge - "Laslo" [Campaign 2, Mission 5]

I assembled an army in 3 weeks, captured all the territory up to one garrison and the entire left winter area, broke through the garrison without losses, encountered a hero (not Laslo) on their territory, defeated him with almost no losses, took a half-empty Hork, also without losses, settled there, and now Laslo is pressing me... My army consisted of about 250 warriors, 180 blade throwers, 92 bear lords, 14 jarls, 21 priests, 5 lava dragons (maybe I named someone incorrectly, but all units are upgraded), I sent a caravan with reinforcements, but it didn't make it in time. Laslo stormed the city with an army: 4 fallen angels, 22 knights of Isabel, 78 battle griffons, 350 land lords, 187 archers, 26 adepts, 100 zealots, and completely crushed me, which surprised me a bit... I reloaded (a few turns back) and, after taking the city, ran back to my territory, but Laslo took Hork and settled there, and doesn't even think about leaving. What should I do? =(

Added after 3 hours 58 minutes
I made it =) I did this: Duncan ran from corner to corner, teleporting to the city when Laslo was close. Laslo didn't receive reinforcements, and I built up my army, eventually gathering an army that was superior to his and defeating him. Then I easily took Hork.