Out of three eufyCams, two are not hearing/recording sound...it was OK for a year!

Hello,
Out of three eufyCams, two are not hearing/recording sound, one of them muted all of suden, the other one had the same issue, cannot hear anything while viewing or recording.
I didn’t change any settings, only one set is working.

-I compared the setting with the functional one, and nothing is different!
-reset is performed but it is the same issue.
-update is the latest.

Please help!

Device Info
Model No. eufyCam
Serial Number T8111H2218390947
Subsystem Version 2.0.6.5-1029-eu
System Version 1.9.3