Filter failure: LOT_SIZE after sending MARKET order with quoteOrderQty

Recently my unit test started to fail that uses test account for spot trading.

I’m calling this endpoint:

And I started to receive this response instead of successfull trade:
“{“code”:-2010,“msg”:“Filter failure: LOT_SIZE”}”

As I saw in the documentation:

MARKET orders using quoteOrderQty will not break LOT_SIZE filter rules; the order will execute a quantity that will have the notional value as close as possible to quoteOrderQty .

It worked 2 days before. I want to buy LTC for 10 USDT. I have checked and I have testing assets available, but suddenly I got this ‘LOT_SIZE’ error.
Please help.

thank you for the feedback. The testnet has different liquidity as the production site. When placing market order with quoteOrderQty parameter, it can fail because there is not open orders in the market to determine the real qty.

So have a try with quantity parameter, it should work.