if you want to use Instamojo in Nexelit cms, At first you need to get your client id and client secrets , you have to setup your Instamojo gateway settings. Go to “Payment Gateway> Instamojo”.
Go to Instamojo.com login to your dashboard. now click on api & plugins. then scroll down to create New Credentials and click on it.
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now select WooCommerce / WordPress click generate credentials.
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now you will get your client id and client secret.