Changing Owner but have no article record

[kp20mar]

Hi Crythias,
When i change owner ticket, the system's run very slow. Then, i refresh the webpage, i see the owner changed, but have no any article record. So, i can't know who change this ticket Owner.
And, when my customer create ticket (no attachment), the system's run very slow, too.
Pls help me. Tks u!

[jojo]

check your logs

[kp20mar]

check your logs

I've solved. Many thanks JoJo