Restricting Changes from Others on My Account

Here is the link-- https://www.imdb.com/title/tt4104132/?ref_=nm_flmg_job_1_cdt_t_3 The proper primary poster is now visible. I changed it yesterday. The Problem is the Lead Actress Tessa Farrell is a nightmare-- even when working with her...and she keeps going in and changing the primary poster that she wants with her name as Director on it. This is a project that I own, wrote, produced and directed. An award winning short DIAMOND. I need some way to LOCK this poster and stop anyone from contributing or changing anything if possible-- especially her!

@tygrandjones​ Hi- Thank you for posting the link of the title! Further actions have been taken to prevent further incorrect modifications. Cheers!