Hi,
You can disable 2fa through environment variables.
Read this post - Not receiving emails anymore so cannot change settings as admin as TOTP is required - #2 by dudanogueira
In case of snap, create a file say named 2fa_disable.env in $SNAP_COMMON (/var/snap/rocketchat-server/common) and add those two environment variables there.
Finally restart the server - sudo snap restart rocketchat-server