Bugs in tutorial batlle

Yesterday I had issues with attacks, as during battles with cities with level 1 fortress it would not show me enemy strength. Then, during the night, 1 battle crusier has basically dissapeared. No battle report. The enemy does not have any navy units, nor artillery. But the cruiser is not where I left it. Now this morning I am launching an attack into a a city that suddenly shows defender strength. Claim 9 units. After the firsts attacks with 37 units, the information shows 2 kills, but the city stats still show 9 units garrisoned. Another city to the north, also showing 9 units garrisoned, has sent reinforcements, 3 units, but still shows 9 units garrisoned.

Any explanation of what is going on?.

Now the city under attack has stopped showing garrison strength.

After the attack, the city shows stats again. It now says 4 units left, and 4 units dead. The reinforment has arrived. As far as I know 9 (garrison) - 4 (dead) + 3 (reinf) = 8. My maths might be rusted but this does not add up

More interesting info. Although I am attacking with 37 u a garrison with 9 units & lvl 1 fortress, in the last attack I have lost 4 units, while the defender claims 4 deaths in the attacks since the start. All defender units are basic infantry, like most of mine, I have a few armoured cars with them.