plot two functions in deferent interval using Mathematica

Question

I plot this function. Now I want change this code that plot the blue graph in center and cut this graph after the dash line and plot black curve out of the two dash line.I need to plot to tree parts.

  eqn[d_Integer?NonNegative, r_, B_, A_, nmax_Integer?Positive] 
  :=Sum[Exp[-n*\[Lambda]]*(1 - r)^n Exp[n*k^2 - k^2*A 
  (HarmonicNumber[n + d] - HarmonicNumber[d]) + 
   B*k*HarmonicNumber[n]], {n, 1, nmax}] == -1 +Exp[\[Lambda]]/r;
   AValues = {2};
   BValues = {1};
Show[Block[{$MaxExtraPrecision = 500},ContourPlot[Evaluate@
Table[eqn[0, 0.25, B, A, 100], {A, AValues}, {B, BValues}], {k, 
-2,2}, {\[Lambda], -0.5, 3.5}, 
FrameLabel -> (Style[#, 14] & /@ {k, 
   "\!\(\*SubscriptBox[\(\[Lambda]\), \(r\)]\)(k)"}), 
  RotateLabel -> False, PlotPoints -> 100, MaxRecursion -> 4, 
 AspectRatio -> 1/GoldenRatio, PlotLegends -> Automatic, 
 GridLines -> {{-0.5, 1.0}, {0}}, 
  GridLinesStyle -> Directive[Gray, AbsoluteThickness[1], 
Dashed]]],Plot[k^2 + Log[0.75], {k, -2, 2}, PlotLegends -> 
Placed[{"\!\(\*SubscriptBox[\(\[Lambda]\), \(0\)]\)(k)+ln(1-r)"}, 
\{.5, .7}], PlotStyle -> {Black}]]