Can anyone help with data recovery from an SD flash drive?

Question

Data recovery

Good afternoon! Need advice from a knowledgeable person. I formatted the SD flash drive (blunted it myself) in a sound recorder-recorder. The flash drive contained the video. When restoring data, it does not find the original folders and files, because the recorder formatted in its own way, and now there are files in the form .055_7286_01_1.RSV and .055_7286_01_1.SLI. That is, the source files are divided into parts. instead of one folder with a 3.6 GB file, 15 files! all *.rsv-files (except the last one, the smallest one) are the same size - 520 meters. *.sli files of various sizes, from 3 to 30 megabytes. Is it possible to restore the original appearance of the folder, or somehow merge these files?
Tascam DR-40 recorder, SONY EX1R video camera.