No puedo imprimir el talón de pago. da error de sistemas

Cuando intento imprimir el talón de pago me aparece:

server error in '/' application.
input string was not in a correct format.
description: an unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

exception details: system.formatexception: input string was not in a correct format.

source error:

an unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

stack trace:

[formatexception: input string was not in a correct format.]
system.number.parsedouble(string value, numberstyles options, numberformatinfo numfmt) +[números]
system.convert.todouble(string value) +62
gp.websocios.web.controllers.consultascontroller.talondepagoaimprimir(string pagoenpesos, string pagoendolares) in c:\global processing\fuentes\ms_argentina\mastersocios.arg - bkp\gp.websocios.web\controllers\consultascontroller.cs:[números]
lambda_method(closure , controllerbase , object[] ) +[números]
system.web.mvc.reflectedactiondescriptor.execute(controllercontext controllercontext, idictionary`2 parameters) +[números]
system.web.mvc.controlleractioninvoker.invokeactionmethod(controllercontext controllercontext, actiondescriptor actiondescriptor, idictionary`2 parameters) +35
system.web.mvc.<>c__displayclass15.b__12() +80
system.web.mvc.controlleractioninvoker.invokeactionmethodfilter(iactionfilter filter, actionexecutingcontext precontext, func`1 continuation) +[números]
system.web.mvc.controlleractioninvoker.invokeactionmethodfilter(iactionfilter filter, actionexecutingcontext precontext, func`1 continuation) +[números]
system.web.mvc.controlleractioninvoker.invokeactionmethodfilter(iactionfilter filter, actionexecutingcontext precontext, func`1 continuation) +[números]
syst