okay i will try to provide every mail example: Like when user creates an account, for email verification we are sending an otp on user's email eg: Your verification code is: 123456 Please enter this verification code for successful account creation on dressdoc. If you are having any issues while creating your account, feel free to contact us by replying to this email. Thank You, Dressdoc Team, Email: support@dressdoc.com If user face any issues, i can not say what he/she will write to us. In our previous system, we are not verifying user's emails, so we are receiving bookings from fake email id. Secondly we want to use this email service for successful booking placed and order summary. eg: When user successfully placed a booking, an email goes for informing him/her with booking details eg: Dear user, Thank you for using Dressdoc. Your pickup is scheduled successfully. Our delivery boy will get back to you in couple of hours. So sit back and relax. Booking Details: Booking No.: 1 Pickup Date and Time: 30/03/2018 04:56:00 PM Delivery Date and Time: 31/03/2018 04:56:00 PM Thank You Dressdoc Team Email: support@dressdoc.com For oder summary, i can't predict now, because it's based on type or order. For support, we want to resolve customer queries of any. We are sure that we do not need email for advertisement/marketting. That's why i posted the mail() function issue, because we need emails and our emails were going to user's spam folder. We think of pirchasing gsuite for it, but we don't have enough money to do so as we are not earning from our service. Now i think i included most of the information about this. Krydos please reply with your decision.