Be careful when shopping around, as multiple credit aplications leave 'footprints' on your credit file and lenders will look at how many applications you have made in recent weeks / months to assess your application with them. More than 3 or 4 in the preceeding 12 weeks will almost certainly cause you issues in being accepted.
To explain this, see it from the lenders viewpoint, they do not know if you were accepted or not with your previous applications so usually take the presumption that you are 'credit stacking' - i.e. uptaking mass credit,which is a big indicator of possible credit fraud / abuse.
Leave it 3 monthsand then try again if you fall into the above category at all.
I agree with the above comment about PPP, but I do not agree with using Freedom - they will charge you a broker fee and place you with a higher interest lender. The fee alone will add around 1% to the APR and be interest bearing for the term of the loan.
Are you on the electoral roll? Do you have less than three addresses in the last six years? Do you always make payments to your cards on time? If the answer to any of these is 'No', there will probably lie your problem, as banks use all of these factors to assess your application.
Try going to Black Horse, northern rock ,Halifax or Lloyds TSB.
Good luck