they first sent text (no number to block) about "bitcoin" then got three phone calls from this number using same name that was in text; delay before they spoke; they said '... insurance' - very noisy background sounded like call centre but not off-shore - local accent.

Called but left no spoken message, but sounded like a call centre in the back ground.

I called back number (03) 8306 4858 rang once then goes to busy tone.