WHMCS plugin for SMS notification and OTP

WHMCS is an all-in-one client management, billing & support solution for online businesses. Handling everything from signup to termination, WHMCS is a powerful automation & support tool.
For WHMCS version 7.6.x & 7.7.1: https://www.whmcsservices.com/msg91.php
For WHMCS version 6.2 to 7.4: https://marketplace.whmcs.com/product/1118

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