Frozen account.

 
I have had a good trade for the last 4 months. After this period, my platform sent me something like this:
Dear Users! You need to pay 5% of the funds in your trading account by recharging as the handling fee for unfreezing your account. Only after unfreezing can your trading account return to normal.
What do you think about it: it is normal or a scan?
They have frozen my account
 
Krzysztof Żarski:
I have had a good trade for the last 4 months. After this period, my platform sent me something like this:
Dear Users! You need to pay 5% of the funds in your trading account by recharging as the handling fee for unfreezing your account. Only after unfreezing can your trading account return to normal.
What do you think about it: it is normal or a scan?
They have frozen my account

Contact the regulating authority of your broker - we can't help you here.

 
Mel Gibson:
I have had a good trade for the last 4 months. After this period, my platform sent me something like this:
Dear Users! You need to pay 5% of the funds in your trading account by recharging as the handling fee for unfreezing your account. Only after unfreezing can your trading account return to normal.
What do you think about it: it is normal or a scan?
They have frozen my account

I heard about an inactivity fee, but never a percentage charge on the account balance.

It doesn't sound good I must say, follow Carl's advice.