Lost Sub Folders

Hello, I am hoping someone can kindly help me. In the process of copying folders from POP to IMAP in order to make my account accessible on my new Andriod IPad, my sub folders disappeared the next the day on my POP account. I had not yet started to copy sub folders to IMap. I cannot find them in the Trash and I fear I may have deleted anyway. Is there anyway I can find these missing folders? I am sure I did not delete anything except maybe Trash emails. Thank you for any help Martyn