V5.0 not booting

[df5sf]

Hello, hardware is RaspberryPi 4 Model B (from 2018) with 4 GByte RAM and software remsdr_v5.0_rpi4 on a 16GByte SD card. The software hangs at booting. The red led and green led is blinking for some seconds. Then red led on, green led off. In the router I cannot find any IP. I think my hardware is ok, because Raspbian Pi OS (bookworm) from 2023-10-10 is working ok with the same SD card.. Any suggestions. Thanks Uli