WordPress Security Expert Needed — Find & Remove Possible Backdoor

I have a WordPress website that appears to have been compromised. Suspicious PHP files are being created/modified on the server repeatedly, including files containing heavily obfuscated code such as eval(), base64_decode(), and gzdecode(). I need an experienced WordPress security expert to: Perform a complete malware/backdoor scan Identify the actual source of the vulnerability Check WordPress core, plugins, themes, PHP files, .htaccess, cron jobs and database Identify any hidden backdoors or persistence mechanisms Remove malicious code/files safely Verify that the website is clean and cannot easily become reinfected Provide a brief report explaining what was found and what caused the compromise Recommend security measures to prevent future attacks Security tools such as Wordfence, MalCare, Astra, or other professional malware scanners may be used, but I also need manual code-level investigation. The main goal is not simply deleting suspicious files. I need to identify and fix the root cause of the repeated infection. Please apply only if you have previous experience with WordPress malware cleanup, PHP backdoors, and compromised websites.