Dell refund question

So I started a refund on 10/08/2019.

The package was safely returned at Dell and I got a confirmation that a credit of x amount has been posted to my original mode of payment on 10/20/2019. But it’s been 2 weeks since and I haven’t see anything in my account yet. I tried to contact customer to get an estimated time frame but all I got was “please wait for us in 2-3 minutes while we check..” and they kept saying it for an hour. In the end, I got a credit memo, but no answer to my question. 

So how long will it take for the money to be posted in my account for real?