Hi PM Community,
I know there is a lot of confusion surrounding purchasing add-ons. As I needed to add a couple of US Roaming Add-ons for myself anyway, I decided to make up a how-to guide. A few little details have changed along the way, so this is current as of Nov 15, 2017.
As I said, it's US Roaming add-ons I wanted, but the steps are the same whether you want 1 add-on or multiple, and regardless if they are domestic or US Roaming add-ons.
Let's get started.
Step 1: Funds
Step 1.1: Sign into your self-serve account.
This lands you on the Overview page:
Here, you will see I had a starting Available Balance of $20 (in the blue box). I added this to my account a few weeks ago to test the manual top-up process, but normally I carry don't carry more than $0.00 of Available Funds. Your number may be $0, or it may be something else entirely. Do make note of what your starting Available Funds balance is. (For more info on Available Funds, see here.)
On this Overview page, click on Plans and Add-ons (in the green box).
Step 1.2: Start the process on the Plans and Add-ons page.
Here you can see again my available funds, and my current add-ons prior to the purchase. You may have none showing, or several. It varies from person to person and time to time. You can see I just had a long-distance add-on already (in the lower blue box)
On this Plans and Add-ons page, click on My Add-ons button (in the green box).
Step 1.3: Select which add-on(s) you want to add.
Here you see the menu of add-ons you might like. I personally chose the US Roaming Talk + Text bundle for $15, plus the US Roaming 1GB data add-on for $20:
Notice the box in blue at the bottom. This is relativley new, and is telling you that the process is indeed two steps; it says: "1. Add funds to your account, if you don't have sufficient funds. 2. go back to the add-ons page and select your add-on".
At this point, use the + button(s) to select the add-on(s) you want, and then click the Make a Payment button (lower green box)
Step 1.4: Make a payment (if needed).
This step is only needed if your Availalbe Funds balance (noted earlier) is less than the total of your selected add-ons in step 1.3. If you have sufficient available funds, you can ignore this step and the next, and you'll be taken right to step 2.
At this point, you need to click the Submit button (green box) to process the payment.
Step 1.5: Payment successful - so first half of process is done.
Here you can see the message (in the blue box) at the top of the dialog, telling me that my payment was successful.
I noticed that the Submit button (red box, with line through it) is still enabled here. Based on the fact that the Amount to Add amount still shows $15, that if you were to click this button again, it would process a second payment, which you don't need. I didn't actually try it to confirm that, but I'd recommend you don't touch it.
You can see that the Available Funds amount for me has been updated to $35 (in the purple box), reflecting the addition of the $15 payment I just made, to the $20 Available Funds balance I already had. This $35 is exactly what's needed to pay for my add-ons (in the next step).
At this point, you need to click on the Go Back link (why isn't it a button?!?) (green box) to actually make the purchase from your newly added funds. This is the second of the 2-step process.
Step 2: Purchase
Step 2.1: Purhcase the add-on(s) from your available funds.
Now you have the necessary funds added, you have to complete the second step of the 2-step process.
After having clicked Go back at the end of Step 1.5 above [OR: you may have landed here directly if you already had sufficient Available Funds to pay for your add-on(s)], you land back at the add-on selection page. Notice that the button at the bottom (green box) had changed from "Make a Payment" (as noted in Step 1.3) to "Buy Add-ons".
Please click Buy Add-ons button (green box) to get the final confirmation box to complete the purchase.
Step 2.1: Confirm Purchase (finally).
You should now see a confirmation dialog box showing you your selected add-on(s), and the amount to be deducted from your Availalbe Balance (blue box).
Go ahead and click Confirm my purchase button (green box) to complete!
Step 2.2: Success confirmation.
At this point, you should be returned to the My Plans and Add-ons page, with a notification that the additions were successful (blue box). Notice also my Availalbe Balance now sits back at $0.00 (other blue box).
Click the RETURN TO OVERVIEW link (green box) to go back to the main (Overview) page.
Step 2.3: View your newly added Add-ons!
The final verification is to return to the Plans and Add-ons page and make sure that your new add-on(s) are listed in the My Add-ons section of the page (blue boxes), along side your existing add-on(s) (if any).
DONE:
Congratulations, you've just purchased [an/some] Add-on[s]! 🙂
TLDR 
