Oh no, first Im going to tell you I had that same thing tried on me, the address must be under 45 letters for it to go through the eBay postage label and wont print otherwise and shows up to you as a improper address, the person that tried this on me was from India and when I was trying print I also received the message you did, I sent the screenshot of what I was seeing and asked her to correct the address because when I started to do it inside the postage labeling window I had a message pop-up from eBay telling me if I hand changed anything it would void seller protection.
This caused a red flag to pop for me (only because I've been burned before in other ways) so I sent the message to her to change it, she was including not only commas but an extra sentence "right across from the academy" I went back and forth with her for a full day, I cancelled the sale the next day because she would NOT comply just kept sending me her address for me to change; , I was kind but I knew the woman was up to no good, she had asked me to leave her good feedback immediately after she paid (first red flag) I have learned to wait until they have received and approve of their purchase first and then return the feedback, I created a small thank you outlining this,so I told her that and a copy below is what I use you can have it or modify it to your taste but stick to it its a better option. I feel they ask for it to prevent any feedback reply later
You are the victim of the same scam right now, the best advice Im going to give you came from another scammer I dealt with successfully, she had tracking confirmed delivery and told me she never received it and she lived in a building and someone must have taken her mail, I knew she was lying. I kept the conversation very business like and you can do the same because Pureto Rico is a USA territory so it falls under United States postal laws, stealing via the US postal service is a very serious FEDERAL offense, very very serious, you must use the key words to convey to her how serious it is and that not only will you be filing a case with the US postal service but you will also be calling her local police department to file a charge of postal theft not against her but that it must be reported and you will be giving them her address and name so the POLICE can come by and talk to her to confirm and file a United States postal theft, I did this to my scammer and she immediately told me "no its OK Ill just accept the loss" and I'll put up flyers to ask if anyone has seen my mail" this was a 20.00 lipstick, so you see I do think if you can remain professional and authoritative using key words like United States postal federal offense, post master, local police, her address,and the fact that pureto rico is a US territory when speaking in correspondence with her spell out every word no abbreviations, that keeps it authoritative. .... You may be able to scare this scammer with authority's and there is absolutely no doubt in my mind you have a address scam going on, it's exactly the same I just faced not 2 weeks ago, there must be a website that tells them how to steal from eBay sellers for this to be happening again to you. If she insists then keep it going and do file with the post master, do not refund her even partially. Make her go through it with you, ask her to help you with the police when they come to her door, and I am hoping since it's obviously a theft you can wear her down with what I just told you.
Im am wishing you every good luck in the world and I do think you will win if you do what I did.
"
Hello
thank you so kindly for your business,
We hope you're happy with your purchase
We are dedicated to 5 star customer service
We hope you will give us 5 star feedback to help us grow
if for any reason you feel we have not provided 5 star service please
contact us ASAP so we may address your concerns..
We wait to return feedback after we are sure you're happy..
Thank you again... "
this item was at and over 250.00 and you did not get a signature confirmation, if that's that's the case my friend, your screwed. 
Ebay and papal require signature confirmation for items over the amount of 250.00, 250.01 is over, and even with tracking if they say empty box or did not receive they will get your item and the money from your pocket. This is a very expensive lesson so I am hoping your total was not in the price range I mentioned.
I bet you wont ever hear from that person again.. funny when you mention bringing law enforcement in they go silent 
, you were very lucky!! Thank you so much for telling me and keeping me up to date!! I have a grown a bit cynical at times and its good to see just a real down to earth honest mistake.. 🙂
