https://github.com/code-423n4/2022-03-biconomy/blob/main/contracts/hyphen/LiquidityFarming.sol#L109-L117
The function name implies that the sent amount should be returned, but it uses the amount received by the recipient instead.
If a fee-on-transfer token is the reward token, the amount sent vs received would differ.
Decide which value is to be returned and logged. Either update the function to be _sendErc20AndGetReceivedAmount() or change it to use the contracts balance difference instead.
