I tried to make a new phone number with a new SIM card but I cannot activate that with all of my credit cards. I can use my credit card well on another site so I'm not sure what the wrong is. Please check that issue.
Again, I cannot sign in to my existing account as well. Please let me know a temporary password to sign in to my account and reset my password.
Public Mobile has web page cache issue so you might be looking at obsolete status. Try using different browser. Try Incognito mode. Clear browser’s cache. Try forced refresh. Use computer and not phone to log in.