No USB connection - phone not seen!

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Tried installing Phosh via pmbootstrap and finally got a dmesg awknolegment of the phone on usb.

[ 5215.995226] EXT4-fs (sdb2): mounted filesystem with ordered data mode. Opts: (null)
[ 5216.517404] EXT4-fs (sdb1): mounting ext2 file system using the ext4 subsystem
[ 5216.523174] EXT4-fs (sdb1): mounted filesystem without journal. Opts: (null)
[ 5322.801551] EXT4-fs (sdb2): mounted filesystem with ordered data mode. Opts: (null)

[ 3682.708035] usb 1-1.5: new high-speed USB device number 6 using ehci-pci
[ 3682.817674] usb 1-1.5: New USB device found, idVendor=18d1, idProduct=d001, bcdDevice= 5.07
[ 3682.817679] usb 1-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 3682.817682] usb 1-1.5: Product: PINE64 PinePhone
[ 3682.817684] usb 1-1.5: Manufacturer: PINE64
[ 3682.817686] usb 1-1.5: SerialNumber: postmarketOS
[ 3682.922242] usbcore: registered new interface driver cdc_ether
[ 3682.927151] rndis_host 1-1.5:1.0 usb0: register 'rndis_host' at usb-0000:00:1a.0-1.5, RNDIS device, be:9d:4e:c9:90:79
[ 3682.927174] usbcore: registered new interface driver rndis_host
[ 3682.954316] usbcore: registered new interface driver rndis_wlan
[ 3682.958916] rndis_host 1-1.5:1.0 enp0s26u1u5: renamed from usb0
[ 3683.004472] IPv6: ADDRCONF(NETDEV_UP): enp0s26u1u5: link is not ready
[ 3687.094429] usb 1-1.5: USB disconnect, device number 6
[ 3687.096033] rndis_host 1-1.5:1.0 enp0s26u1u5: unregister 'rndis_host' usb-0000:00:1a.0-1.5, RNDIS device

I wonder why usb disconnected?