Experienced reseller new to poshmark

Hello everyone! I've been very actively reselling on depop for a bit now and I just started crosslisting to postmarked and ebay. What is with all of the bot spam accounts flooding my comments and messages trying to get me to "verify my account details"? Is this normal? Also every time I list something there's like 30+ shares from random people within the first like 5 minutes. And what does it mean if someone adds to a bundle?

Sorry for so many questions and if they are dumb questions! I've heard so many good things about listing on postmarked so I just want to know what to expect.