Is working for a postal distribution company that distributes publications and letters to institutions, including gambling centers, permissible or impermissible, and is the money saved from it permissible or impermissible?

The means take the ruling of their ends. Every means that leads to something forbidden is forbidden. It is not permissible to cooperate in sin and transgression. Delivering papers and printed materials related to gambling, or bank messages that support their activities, is considered aiding in a forbidden act, and the earnings obtained from it are unlawful (haram (definition)). If it is possible to refrain from delivering these messages and restrict oneself to what is permissible, then remaining in the job is permissible. Otherwise, it is obligatory to leave it, except in cases of extreme necessity that prevent you from providing the necessities of life for yourself and those you support. In such a case, it is permissible to remain in the job until one finds another. The forbidden portion of the earnings must be disposed of by spending it on the interests of Muslims, such as aiding the poor and needy and building charitable Islamic schools. This portion is determined based on the proportion of the forbidden work.