TPS like it's sister company the
DPS (which covers mailings) is a bit toothless; it's funded by the Marketing Industry, and can't cover calls from overseas numbers, even Ireland.
Also some telesales companies say when challenged, or
we're not selling, we're carrying out a
survey, which gets round the Regs.
My phone has a "Hold" facility so you can talk to someone in the house whilst keeping caller on hold;
this has benefit of playing caller dreadful electronic music; I leave them to it, and hang up a few minutes later!