Probably me as my son is one. Just had a chat with him and if Evostick (but which sort and did you allow enough time plus a bit to cure?) did not work he suggested Loctite Vinyl, Fabric and Plastic. Need to make sure clean, no dirt and leave it long enough. However some fabric can be so old the only solution that will last is a new one, and that includes having got a sailmaker to sew it up; a quandry he frequently faces with boat owners who think everything is repairable which it is but, to mangle a quote, 'you'll be back'.
Dick