for any questions don't hesitate to send me a message

I want to end a formal letter and I want to say:
"... for any questions that might arise don't hesitate to send me a message / connect with me / communicate with me ..."
I think Russians do this by using the the verb:
обратиться с вопросами

Please some help

The translation would be: "по всем возникающим вопросам обращайтесь по мейлу (по телефону) ... "