Unfortunately, you cannot change your account type of the platform you have selected.

If you wish trade in another account type or platform, you will need to reopen trading accounts again.

For your information, you can have up to 8 live trading accounts under the same email address.

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Please note that MT4 and MT5 trading platforms are provided with two different trading servers, thus you cannot login to MT5 platform with MT4 account and vice versa.