International SMS api Setup in website for OTP verificaiton

I am looking for a freelancer to help me set up an International SMS API for OTP verification on my website. The primary programming language of my website is not a concern, so any stack will do. I am open to suggestions for the SMS API to be used, but would prefer not useTwilio, Nexmo or Plivo. In addition to OTP verification, I would also like to have SMS notifications set up. Ideal skills for this job would include experience with SMS APIs, website development and integration, and knowledge of web security.

Not Plivo or twillo or nexmo charging more, So i want to use different API for different countries or suggest me one better SMS provider who charing less, I can buy a Phone number from them for sending SMS from Local numbers.

Hope you understand.

Thank you