@Vincent-TP Many thanks for your kind reply , however i didnt know it was not recomended to use as bridge/repeater mode ,

and as this modes was in quick setup and i was using very happy till last update.

and as i advised another cpe220 with first firmware i.e CPE220UN.V3.20201028 still working very stable.

i tried different channels as you advised in main router unfortunetly again same problem

i will update firmware with pre-release and hope this will fix

i wish i have chance to return first firmware but looks unfo no any chance

i will keep you informed if pre-release will help

thanks in advance

  @Vincent-TP i have tried  loading prerelease unfo not able to do , screen picture as attached

  @Vincent-TP  yes i did

  @Vincent-TP yes i have loaded from that link

i took the risk and tried to upgrade the other cpe220 in my hand with same file (prerelease)

upgraded without any problem , i hope i will not have same connection problems while using

in bridge mode.

the problematic cpe 220 i tried as you mentioned another browsers / private modes etc

unfo not accepting file , what i have noticed is cpe 220 only accepting the firmware file which 

is inside , not accepting any other firmware i.e screenshot as attached.

what i have tried is

- loaded firmware given link from 3 browsers

- tried to upgrade with 3 browsers 

unfo always same not accepting file

pleased to hear