dsl works for a day or two then errors

I have 80/40, I had 40/20 . Both services worked for a day or two,then large numbers of errors. Had three wide band techs out. I am 1070 feet from box. The techs switch my dsl lines, it is perfect for a day or two and then large number of errors. I have dsl lights going red. sometimes line two dsl would go to 20/5 . I am in sun lakes Az. It is very frustrating for me. I use chat to get help, they check lines and say very bad and dispatch tech.