binance "code":-1022,"msg":"Signature for this request is not valid. shell script

hi guys i try to many day to run this code but returnme always code":-1022,"msg":"Signature for this request is not valid , but i am sure is correct a code , anyone can controll my script for see if is all ok ?? thanks at all for advice

APIKEY="MY APIKEY"
APISECRET="MY SECRET KEY"
URLPART2="symbol=BNBUSDT&side=BUY&type=LIMIT&quoteOrderQty=10&price=270.3&stopPrice=270.3&newOrderRespType=FULL"
RECVWINDOW=50000
RECVWINDOW="recvWindow=$RECVWINDOW"
TIMESTAMP="timestamp=$(( $(date +%s) *1000))"
QUERYSTRING="&$URLPART2&$RECVWINDOW&$TIMESTAMP"

SIGNATURE=$(echo -n "$QUERYSTRING" | openssl dgst -sha256 -hmac $APISECRET | cut -c 10-)
SIGNATURE="signature=$SIGNATURE"

#curl -s -H "X-MBX-APIKEY: $APIKEY" "https://api.binance.com/api/v3/order/test?$URLPART2&$RECVWINDOW&$TIMESTAMP&$SIGNATURE"
curl  -H "X-MBX-APIKEY: $APIKEY" -X POST "https://api.binance.com/api/v3/order/test?$URLPART2&$RECVWINDOW&$TIMESTAMP&$SIGNATURE"
echo```