2001 Yaris 998cc not engaging in 2nd, 4th or reverse, already had clutch replacement

[ManxYaris]

Hi all

I have a 2001 Yaris, 998cc model. Had clutch replacement kit put on car last June 2022 as gears kept slipping. After the garage fitted the new clutch I had an issue with gears 2 days later where it wouldnt engage in 2nd or reverse gears, took it back to the garage who said the cables went bent and that they had straightened them, had no issues until 3 days ago where i lost 2nd 4th and reverse gears. My son looked at car and the gear cables are overstretched.

What could now be the issue, do i need new gear cables, or could it bei need a new gearbox? Garages these days cost a bomb to even just look to see what the issue is.