Epic battle leading to forever frozen AI turn

Context : i'm playing Hayasdan, there was a race for Mazaka between Ptolies, Arche and me, the Arche eventually conquered it first, after what the Pontic kingdom (my ally) declared war and besieged Mazaka with 1,5 full stack, so i put my own stack just next to his and started besieging too as a good ally.
Then the Arche basileus himself came with a huge stack, and with the help of the full stack already in Mazaka attacked the Pontians, who requested my help in the battle.

I did. (you have to click on "reject" to accept, strangely, found out after several reloads)

Sooo I just finished this HUGE and crazy battle (4,5 stacks, 12k soldiers), Arche crushed Pontos and overall played very skillfully (the 2 elephant units who entered just behind my battle formation were a nightmare to manage as I was clashing with the full stack from the city), but eventually I won.

Pontos faction leader was killed.
AS faction leader was killed.
AS faction heir was killed too, I believe.
Arche could have avoided this but it couldn't pay the 27k ransom i was gently asking.

So. Now, the game is forever blocked at Arche turn. Maybe the succession war is going on. This is not a crash. I can open escape menu, move through the map, it's not crashed, just forever frozen.

What can I do ?




the current situation :

It's been frozen for more than 1 hour now. I can't remember if it's normal or not, but the 2 armies sieging Mazaka have a tremor every 30 sec, the attacking movement, but very briefly.

Lol, zoomed a bit and srsly look at them.
What a weird dance



There is even conjoined fraternal twins - with one missing banner
So it's frozen right in armies movements