This looks very serious, and is probably something that should be reported to the police. It appears from a Google search that there are two companies, with remarkably similar names. They are:
Portfield Finance
149 Wellgate
Rotherham
S60 2NN
Tel: 01709 828506
Fax: 01709 372691
Portfield Financial Services
Unit 8-11
Ashley Business Court
Rawmarsh Road
Rotherham
S60 1RU
However - read on. Google also has this link to a report of a known scam:
http://listserv.cnr.it/cgi-bin/wa?A2=ind0411&L=linux-it&P=18418It is clear from this link that a "419" scam has been operated from the same premises as the first of those two companies, using mobile phone numbers, rather than landline numbers, a sure sign of something illegal. It would be best to have nothing to do with any of this.