unable to compile basic arduino scripts

[skywo1f]

In file included from C:\Users\iviti\sketchbook\libraries\MyCobotBasic/bits/stl_construct.h:59, from C:\Users\iviti\sketchbook\libraries\MyCobotBasic/bits/stl_tempbuf.h:60, from C:\Users\iviti\sketchbook\libraries\MyCobotBasic/bits/stl_algo.h:62, from C:\Users\iviti\sketchbook\libraries\MyCobotBasic/algorithm:62, from C:\Users\iviti\AppData\Local\Arduino15\packages\esp32\hardware\esp32\2.0.6\cores\esp32/Arduino.h:162, from sketch\Move_Robot.ino.cpp:1: C:\Users\iviti\sketchbook\libraries\MyCobotBasic/new:40:10: fatal error: stddef: No such file or directory