I use the Tezbox wallet and have tried to change my delegate and I thought followed the instructions exactly, but even after 6 days now I am still receiving rewards from my old Delegate instead of the new one.
I went to my staking wallet starts in KT selected the delegate tab and then changed the custom delegate to match the new Baker's address. When I log out and log in again the new delegate address appear is my custom field and if I view the address on TZscan it also shows me the new Delegate address in the Delegate field on the right-hand side so I am now stuck as how to proceed.
Can anyone advise if they have succesfully changed delegates and how it was achieved?
For what I can understand from your post you did everything correctly : you will still receive the rewards for a certain number of cycles from previous baker you delegated to and then you will receive rewards from the new one.
If you remember the first time you delegated your Tezzies you had to wait a certain number of cycles before starting to receive rewards : now you will receive from the old one for the same number of cycles and then you will switch to new rewards.
The schedule is the following:
Cycle 0 - you delegate
Cycle 7 - The Tezos Blockchain assigns your delegation rights to chosen baker and they can start baking for you.
Cycle 13 - Rewards for Cycle 7 are received by baker and forwarded to your KT1 account.
Anyway to look deeper into your own situation go on tezscan, fill in your KT1 address and click on "RewardS" tab.
Hope this helps.