What should I do if the "Tongcheng Travel" app cannot be opened in Japan? Can a VPN or accelerator solve this problem?

What should I do if the "Tongcheng Travel" app cannot be opened in Japan? Can the return to China VPN accelerator solve this problem? In today's globalized world, more and more Chinese people choose to travel, study or work abroad. However, Chinese people living abroad often encounter a common problem: they cannot use domestic applications normally...