TL-R480T+ V8 constantly releases Dynamic Wan connection and can't obtain it again automatically
I have TL-R480T+ V8 Load Balance Router and use 2 Wan ports. First Wan is PPPoE connection and Second Wan is Dynamic Ip.
I have problem with Second Wan that uses Dynamic Ip, because it constantly releases and can't obtain new ip automatically, but I need to obtain it manually by pressing Obtain button in Wan 2 Settings page.
Can you please help me or guide me how to resolve this annoying problem.
Thank You in advance.