Set gwei to 250 but fails

Hey there,
I have a application that works with a marketplace.
I want to set the max Gas limit to 250 gwei and I want it to take only as much as it needs but it takes always 50$.

     gasLimit: this.web3Js.utils.toHex(1000000), 
      gasPrice: this.web3Js.utils.toHex(this.web3Js.utils.toWei('250', 'gwei')),

I dont understand why it always takes 50$. I want to set the limit to 250 gwei and only take as much as it needs but my code here always takes 50$. I lost 100$ because of this

hello ?
I need help please

nice support. Dissapointing

try it on a local devchain first or on a testnet, if you set that gas price then it may use that gas price, try with 100 or with 50 if you want lower gas price