Solve an integro differential equation

[kpreethimaths (K PREETHI)]

Consider the following code:

In[1]
    eqn = f2[w] == A + (\[Lambda]/k*\!\(
    \*SubsuperscriptBox[\(\[Integral]\), \(Q\), \(w\)]\(
    \*SuperscriptBox[\(e\), \(\(-\[Mu]\)*\((t - w)\)\)]*
            f2[t] \[DifferentialD]t\)\));
    sol = DSolveValue[eqn, f2[w], w]

But I got this answer

Out[2]
A + (\[Lambda] \!\(
\*SubsuperscriptBox[\(\[Integral]\), \(Q\), \(w\)]\(\(
\*SuperscriptBox[\(e\), \(\((\(-t\) + w)\)\ \[Mu]\)]\ f2[
      t]\) \[DifferentialD]t\)\))/k

f2a.nb (3.37 KB)

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[mariuszi28cg (Mariusz Iwaniuk)]

Mathematica 12.1 also can’t find solution.Using Maple 2020: