Check your hardware, TV, cable and device:
2021-03-11 15:32:39.116 T:4878 DEBUG <general>: CecLogMessage - << Broadcast (F) -> TV (0): POLL
2021-03-11 15:32:39.116 T:4878 DEBUG <general>: CecLogMessage - << f0
2021-03-11 15:32:39.145 T:4878 WARNING <general>: CecLogMessage - Write: write failed
2021-03-11 15:32:39.145 T:4878 DEBUG <general>: CecLogMessage - << f0
2021-03-11 15:32:39.184 T:4878 WARNING <general>: CecLogMessage - Write: write failed
2021-03-11 15:32:39.185 T:4878 DEBUG <general>: CecLogMessage - >> POLL not sent
2021-03-11 15:32:39.185 T:4878 DEBUG <general>: CecLogMessage - TV (0): device status changed into 'not present'
Looks like no CEC connection at all!
Same issue was here: