Bots are unfortunately a problem here on DA that is everything but stopping as I'm writing this journal. DA doesn't have a function to report accounts, but we can still deal with them in other ways.
"How do I recognize a bot?"
They have no info on their profile and they send to artists fake promotions like these in hope to hack their accounts, some of these will auto-deactivate after some time, sometimes multiple accounts will send you the same text at the same time:
"How can we deal with them?"
First of all NEVER click any of the links they send you, then block them, I'm not sure if contacting the DA @team will help but I guess it doesn't harm trying.
UPDATE 07/20/2022 Thanks to @jkrolak for the info!
DA does have a way of reporting bots:
Go to Contact DeviantArt (deviantartsupport.com), under Contact us / Submit Ticket
You need to EXACTLY tell DA why you believe this to be a bot account. Just saying, I think it's a bot won't work. You need to show that it either promotes spam