I'd love to teach Maths but have an Accounting DegreeWatch
One option might be to complete a Cert of HE in Maths with the OU to give you the required number of credits needed to do the PGDE Maths. In Scotland it’s free if you earn under 25K. It can be done over a year or two depending on your other commitments. Other places may offer a maths Cert HE also. You may want to double check with universities that offer the Maths PGDE that it would be accepted though.