Developers
Check the chain id, 143, before you send. Check the block timestamp if a contract you copied used it as a minute-scale clock. A 150 million gas block is room, not a reason to set a huge gas limit. Your transaction should still be small.
There is no API key for this site and the server does not sign. A successful eth_call is not a fill. Wait the receipt for a payment you cannot unwind. For a close you can trade again, the hash is enough to update the screen, and a second copy is how you sell twice.
Addresses belong to the token list, not to a ticker in a comment. WETH does not unwrap to MON. USDC has 6 decimals. WBTC and cbBTC have 8.