curl --location --request POST 'https://api.kucoin.com/api/ua/v1/unified/account/modify-leverage-margin-cross' \
--header 'Content-Type: application/json' \
--data-raw '{
"currency": "string",
"leverage": "string"
}'{
"code": "200000",
"data": {
"currency": "BTC",
"leverage": "5"
}
}