My Biggest Complaint About Cell Phone Roaming in Spain

I recently changed my sim from Movistar (I live in Spain) to Talk Out, porting my number and found I was now continually roaming and the cost was 10 times as bad as Movistar ! So I changed to Lebara and ported my number over yet again. I still have roaming on although Lebara inform me I am not on roaming charges … I went to the UK last week, turned on my phone and the roaming sign had gone and so had Lebara ! so I put in a UK Lebara sim card only to get the message “restricted service “. I could not use my phone at all. I returned to Spain and yes I am back to a working Lebara network with ROAMING. WHY ? My phone is a Bang and Olufson Serene and I have used Vodaphone and Movistar with any problems at all in lots of countries.
Suz