LM358 waveform generator issue
Your resistor values are too low. Try about 10x the given values and reduce the capacitor proportionally to compensate.

R34 is too low in relation to R36. The op-amp does not swing to the power supply rails.

The op-amp you've chosen is not fast enough for the integrator function, let alone to be used as a comparator at tens of kHz. Note that many op-amps perform badly as comparators, and as well may present a very low impedance to differential voltages of greater than a diode drop or two.


Here is what it looks like operating, albeit at ~1/100 of your desired frequency:

With 10K/15K/5.2K/100nF