Hi there does anyone know why skoda octavia 1.6 tdi 20 11 have low power  and sometimes cut power  thanks .

Well the first thing would be to check the basics: air and fuel filter, MAF sensor, the battery and alternator. Did you read the fault codes or had someone done it?

Also, check whether the engine is overheating.

There’s too many possibilities to guess without reading fault codes and further info.

Did you find out in the meantime?