Z VISA REQUIREMENTS

On the 28th of september the embassy announced that foreigners can return to china. Everytime it changes, they say just a normal z visa submission, then I need a PU letter, then even with a PU letter I cant get it. Chinese government announced nothing about a PU letter for expired work permits and residency and now I have a new work permit and letter of invitation. I cannot get hold of the visa department to ask questions because nobody answers the telephone. Please assist me if you can.