yealink sip-t19p does not go to the web interface

[AlexeySafronov]

Hello!
there is a phone yealink sip-t19p. it does not go to the web interface in the browser (the wheel turns for a long time and chrome writes 500 internal server error, in other browsers the wheel turns for a long time), although it pings and gets the IP address via DHCP normally (when connecting to different routers, it gets different IP addresses, for example 192.168.0.100, 192.168.1.34). I tried different browsers, cleaned browsers, and even tried on different computers. The phone settings were also reset to default (I kept the Central button for a long time and confirmed the reset with the OK button when asked). tried to flash through TFTPD, pressed the speakerphone button and turned on the power, entered all the settings (previously repeatedly flashed phones with Rostelecom-the procedure is familiar) writes network failed and after 3 seconds loads the phone in normal mode. please tell me what you can do. Thanks!!!!!