error: 'ledc_timer_config_t' {aka 'struct <anonymous>'} has no member named 'bit_num';

[nullbeing]

I have a M5stack Camera F ,trying to load the wifi_sta program,when make compile, error occur:

error: 'ledc_timer_config_t' {aka 'struct '} has no member named 'bit_num';

[EeeeBin]

Pls try esp-idf v3.3