Bajaj Finserv — "dear customer, we regret an otp cannot be generated due to a requirement of fresh nach (ecs

I've applied for bajaj finance emi card also paid 399 rupees after 10 days i got the emi card with number [protected], i got an email by bajaj finance that i have to submit my documents to the courier person, i've done it. And when i tried to use the card on website it said

"dear customer, we regret an otp cannot be generated due to a requirement of fresh nach (Ecs) mandate. Visit the nearest branch for submission of the nach mandate. Use alternate payment option to complete your purchase. Rgds, bajaj finser"

And i submitted all the documents as bajaj finance instructed. What i do now??? I am very disappoint with bajaj finance.