How to increase the credit card Credit Limit ..I am confused?

I am using CIti bank Credit Card
My credit limit which the Bank has allotted was on the basis of mine first job but now i am into my second job and i getting double salary here ….I had a word with customer support people regarding the same ,They guided me to send them the latest salary slip.After doing that also i got a response that they can’t do any thing on it
Kindly be patient may be in future they will increase
can any one guide me what should i do now

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