Spam Text Messages From Email Addresses

Last night and this morning I received two text messages that appear to be some kind of spam. One was a group message that included 18 other numbers, all of which have the same first 6 digits as my phone number. Both messages were also sent from email addresses, however the message itself included an email address that was completely different. One of the email addresses that sent the message actually links back to a legitimate business (a women's shelter).

I'm fairly certain these messages are not at all related to LinkedIn because I don't have my phone number associated with that account in any way. I've reached out to LinkedIn's customer service and am awaiting a response. In the meantime, I'm wondering if anyone else has seen this? I've been unable to find similar posts. I don't want to constantly be receiving these. I blocked the first email address and they just messaged me from a new one. The messages don't include any links, so aside from being annoying I don't think they're dangerous. Although it does creep me out that I have no clue where they found my number.

Screenshots of messages included below.