Apache 408 log entries

In my Apache logs there are lots of 408 entries, it looks like connection to server is ok and then no traffic.

46.114.5.234 - - [09/Jul/2023:10:42:59 +0200] "-" 408 152 "-" "-"

I double checked all settings in apache.conf :

#
# Timeout: The number of seconds before receives and sends time out.
#
Timeout 240

#
# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.
#
KeepAlive On

#
# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.
#
MaxKeepAliveRequests 750

and

evasive.conf:

<IfModule mod_evasive20.c>
  # RKA: Größe der HostHashTabelle, Je größer desto schneller, je kleiner desto weniger Ram Verbrauch
  DOSHashTableSize 8192

  # Request pro Intervall auf eine Seite von einem Host
  DOSPageCount 240

  # Requests pro Intervall auf einer Domain von einem Host
  DOSSiteCount 480

  # Definition Intervall für die Requests pro Seite in s  
  DOSPageInterval 2

  # Definition Intervall pro Domain
  DOSSiteInterval 2

  # Dauer der Blockade in s
  DOSBlockingPeriod 300
...

and reqtimeout.conf:

...
   #RequestReadTimeout header=20-40,minrate=500
   RequestReadTimeout header=30-50,minrate=250

    #RequestReadTimeout body=15,minrate=500
    RequestReadTimeout body=25,minrate=250
...

And feel the settings are not very tight, may be a little bit too loose.

Can someone give me a hint what can prevent the connection data flow further?

Server load is fine, the addresses of the 408 seem to be all mobile or dynamic IP adressess of internet providers like Telekom or dreiat.

I also checked, if my server is on some kind of blacklist but did not find anything.

Hints and help are very welcome, I guess I loose more than half of my traffic to 408.

Additionally, some visitor countries are completely missing, I get never traffic from there but should...

Best regards