So you have no proof you sent any funds from a Bitcoin wallet you own to the Bitcoin wallet of the 1xbit scammers?
First proof is a clickable link to a blockchain website such as blockchain.com/blockchair.com that shows you sent funds from your BTC wallet to the 1xbit scammers.
The second proof is a clickable link to a blockchain website such as blockchain.com/blockchair.com that shows the 1xbit scammers sent funds from their BTC wallet to your wallet.
The third would be for you to sign that address that you received funds from the 1xbit scammers with a message to prove you own it.
First condition is met, paste the ID in your site.
Second condition is also met, cfr first condition.
Makes me laugh that you post these conditions while I already provided them and you seemingly dont know what to do with transaction ID's.
Third, the one I did not meet, got no clue how, so tell me without having to create additional accounts or whatsoever, FYI I use a ledger if that helps.