Hello!

I've been following some of the guides on how to solve linear PDEs and modifying my code as appropriate to get proper boundary conditions and initial conditions. The PDE i am trying to solve is this:

And my code is:

eqn = D[u[x, t], {t, 1}] == D[u[x, t], {x, 2}]; 
ic = {u[x, 0] == 0, Derivative[1,0][u][0,t] == E^t,u[1,t]==0}; 
DSolveValue[{eqn, ic}, u[x, t], {x, t}] 

And the corresponding output is:

I'm not sure if the PDE is too complex to solve, or if I incorrectly entered one of the boundary conditions. I can always get a solution when I don't have derivatives in the boundary conditions, but the documentation of DSolveValue says that derivatives can be used in boundary conditions. Any help is greatly appreciated!