When saying thank you, I know you you say "ありがとう", and "ありがとう ございます" for being more polite, but what's the difference bewtween that (polite version) and "ありがとう ございました" or  "どうも ありがとう ございます". I know there's a few more way, but I'm curious on these ones specifically.

Thanks in advance.

btw if this is explained in one of the lessons, I probably haven't gotten to iut yet. I'm still in later parts of Katakana at the time of writing this.