Sorry to hear you are dealing with this issue. 
Sadly there is no way to retrieve TRP data that is already lost to the wind. Fortunately, there are ways to prevent and protect yourself from it that you can employ for the future.
First off, if you do not have the appropriate cleaning measures set for your TRP3 directory, the addon can very quickly take on an overload of data and end up erasing everything of its own accord. The data the directory saves can be accessed across your entire account. While logged in, one’s directory can accrue dozens or even hundreds of profiles saved in a single play session. This includes not only character profiles, but their mount and pet profiles (known as “Companion” profiles) as well… now compile that with the number of alts you might play regularly, and especially if you enjoy attending larger RP events… yeah. It can get pretty massive. And the bigger the directory, the more at-risk you are for an involuntary data wipe.
I strongly recommend going into your TRP3 Register settings and changing/double checking the option you currently have selected for “auto-purge directory”. This particular setting will purge your directory of other peoples’ profiles you have not actively seen in the world for however many days you set it to. I personally have mine set to two days. You may also be the kind of person that would rather not get rid of EVERYONE else’s profiles - me too! If you don’t want certain profiles to be erased, like your RP partner’s for example, you can simply set a relations status for them, and they will be exempt from the routine purging.
Another protective measure I am a strong advocate for is to create a Google Doc or some other equally accessible file within which you can write up/paste ALL of the necessary info for your character’s TRP profile, along with whatever extra material you like. I have a doc for each character I play.
Not only is this helpful in the case of a TRP data wipe so you can quickly refill a new profile with pre-saved info, it’s also great to have if something bad happened to your entire computer, or if you’re away from your computer and need access to that one really obscure favorite food your character said they liked one time but you the player can’t remember; really a myriad of situations can be aided by the simple act of storing your profile information somewhere safe ahead of time.
My final recommendation to go along with the one above is to save the export code of your TRP profiles. You can access these codes by opening your TRP panel and going from Character -> Profile. Then, click the little red arrow button on the bottom right of any profile (called “Actions”), and select “Export Profile”. Now you can copy all that data, paste it somewhere safe, and import it into the addon again any time you might need to do so!
I have been using TRP3 (and its predecessor, TRP2) for many years. I cannot remember the last time I had to deal with a full-loss data wipe and I like to believe it’s due to these precautions. I hope this post might help you avoid situations like these going forward! 
