Got a three contract a month or so ago. Happy with deal.
Away for a few days so treated myself to a payg broadband on 3. Topped up 15
quid and works well.

These may be simple questions but

If I put my Contract sim in my dongle, what happens next ?

If I put my payg dongle sim in a phone, what happens next ?

I have texted my phone from my BB connection and it worked fine, and from
phone to bb worked too.

I have called my bb sim from my phone and get "number cant accept call"
message. Is this permanantly a BB sim, or can it become a voice sim ?

Ta in advance for those with the time