Forcing Activation Text for iMessage

Long story short, I am in Italy and removed my sim, so my phone number is now grayed out on iMessage. I would like to reactivate it, and I've read that iMessage verifies via a text message. I am now able to send international texts/calls with my original sim, and am on wifi, but I still get an error when it tries to activate.

Any suggestions? Would me sending an international sms help "turn on" the sms feature possibly?

Thanks much in advance!