From this article you will know how to redial calls on the Yealink W52 handset.

The redial number list stores the twenty last dialed phone numbers. When the memory of the redial number list is full, the handset will automatically erase the oldest dialed number when a new number is dialed. You can redial a call from the redial number list.

To redial the last dialed number double press off-hook key when the handset is idle. It will initiate a call to your last dialed number.

To redial a previously dialed number press off-hook key when the handset is idle. The handset will display the dialed phone numbers. Press up or down key to highlight the desired entry. You can press Options > Edit Before Call to edit the phone number or select the desired line by pressing the Line soft key. Press off-hook button again, it will start a call.

You can add local contacts from the redial number list or delete an entry or all entries from the redial number list.

To delete one entry from the redial number list press off-hook key to access the redial number list, then press up or down key to select the number you would like to delete, and press Options > Delete. If you select Delete All from the Options menu, and press Yes when prompted, it will clear the redial number list completely.