Void TextureAtlas::drawNumberOfQuads(long numberOfQuads, long start) crash

after some Interstitial i have crash in some lines or
glDrawElements(GL_TRIANGLES, (GLsizei) numberOfQuads6, GL_UNSIGNED_SHORT, (GLvoid) (start6sizeof(_indices[0])) );
or in memcpy(buf, _quads, sizeof(_quads[0])* _totalQuads); becouse buff is null .
it happen a lot after Interstitial “Game of war” , after other Interstitials its mostly work , that can be problem and how to solve it ?

P.S in iOS only