NSS7 downlink C and Ku signals in Libya

It looks hopeful.  The detailed coverage maps are here:
https://www.satsig.net/global-teleports/north-africa-coverage.htm

The downlink power in eastern Libya is about 4 - 5 dB below the beam peak.  What size dish are you using and what carrier frequency, symbol rate and polarisation are you trying to receive.  I should be able to see your downlink.  I am in the same coverage at the beam peak, so I will see what is the margin here.
wxw
Best regards, Eric.

For C band operation, a 1.2m dish is probably too small unless the service provider is paying extra for more transponder power than is the fair share of the transponder resource.  Think in terms of 1.8m minimum for C band operation, preferably 2.4m or 3.7m or 4.5m diameter.

For your Ku band reception, have a look at the downlink contours and see if the reduction can be related to the locations and contours.  It should be noted that in the edge region of the beam, the contours are only approximate and that level will vary rapidly from one place to another.   The contours vary with frequency as well as with small satellite movement, so it is not possible to be very precise.

A reduction from 55 dBuV to 51 dBuV is an 8 dB reduction in signal power, which I agree is much more than expected.

Sun noise occurs when the satellite crosses over the sun.  This happens in spring and autumn, in each case for several consecutive days at the same time each day.
On the first and last days, when the satellite grazes across the edge of the sun, you may hardly notice the noise increase, which lasts a few seconds.  On the middle day when the satellite goes right across the equator of the sun, the noise increase is the greatest and you may have a short outage.   It depends on dish size, frequency etc.

Best regards, Eric