I deposited 1 SOL (where 1 SOL = $100) for a 5x leveraged SOL-Long position and profited $50 (where 1 SOL = $110). Why did I get less than the full amount?

Assuming zero fees, with $50 profit, you will be getting SOL in return with value of $150. At the time of closing the position, 1 SOL = $110.

$150 / $110 = 1.363
You will be getting 1.3636 SOL where the value is equivalent to $150.

Screenshot of the Deposit/Withdrawal tab

Here is another example, this is a SOL-Long position, the total amount the user should be getting is $3086.28 in SOL.

The value of SOL at the time is $189.28, hence $3086.28 / $189.28 = 16.30. The user will be receiving 16.30 SOL in return.

Note: The PNL shown is the amount before fees. The exact amount is shown under Deposit/Withdraw tab.