LTC M address?

Hello.. I am new to mining as I just started yesterday.. When I entered the payout LTC address, it gave me "Invalid Address" when I entered M-address assigned by Trezor.. However, I converted it to 3-address using https://litecoin-project.github.io/p2sh-convert/.. It accepted.. I wanted to make sure this is correct method of converting.. I would hate to lose the funds due to errors.

Thanks!

all litecoin addresses start with the letter 'L'

the 3 Address is right. Using it myself with trezor. Prohashing does currently not support M Addresses.
Or you could just use the Legacy LTC Wallet of Trezor which uses the L Addresses

UPGRADE to Coinomi

Thanks guys.. Got my first payout and was confirmed it arrived into my Trezor wallet.