D-Link DAP-1620 Manual page 22

1. 
2. Why is my Wi-Fi range extender not connecting with WPS button?
1.  A:
2.
Some routers/modem may have the WPS button disabled by default. You also may need to press the WPS button for a
little longer on your wireless router/AP (5-7 seconds)
If you have already tried the WPS button setup and the LED on the range extender does
not turn green, then try the WPS setup again by following the steps below.
Step 1: Wait for the LED on the DAP to blink amber. Press and hold the WPS button for
3 seconds on your wireless router/AP. (Some routers/AP's may require you to hold it a
little longer)
NOTE: Make sure the WPS/Wi-Fi LED on your wireless router/AP is blinking, after
pushing the WPS button