帮我看看，我写的有没有问题

If you need to add new suppliers, please feel free to let Roy and me know. 如果你需要添加新的供应商，请随时通知我和Roy。

最好写出中文你想表达的意思，这样方便对照修改。

If you need more suppliers, please feel free to inform Roy and me.

if you need new supplier, please let me and Roy know.

Once you need to add new supplier, please feel free to let Roy and me know.
一旦你需要添加新的供货商,请随时通知我和Roy。