You dont say hare in Spain you are, and its a big place. Spain is outside the official transmission footprint for Astra 2D, and different frequencies are received at different signal strengths.
Its quite possible your dish isnt big enough for some of the frequencies.
However ignoring this factor for a moment, somewhere in the receiver menu structure will be the settings for a manual scan
Put the following parameters into it - ignore what the letters mean, you just want the numbers.:
10788
Vertical
SR 22000
FEC 2/3 (may not be there - many receivers do this one automatically)
and allow it to scan. If it comes up with no signal your dish is probably too small.