Sorry for needing help again

I am wondering what the policy in Switzerland is on items that have been wrongly invoiced and delivered.

I ordered lab material, and one of the items was out of stock, I asked it to be replaced by a similar type but they adjusted the quantity without telling me and now my total bill is 80 CHF too much!

I received this large parcel with the extra material in the mail, with an invoice. Now my question is, should I send it back, and ask them to resend the correct parcel/amount, which should be much smaller?

Or do I open the parcel, take out the lesser quantity I should have received, and then send the remainder of the parcel back?

Basically I have no idea how strong my position is on such matters in this country and how to best approach this. (I do want to fight it as money is tight atm).

Have you spoken to or mailed them? Communication of sorts expressing your extreme dissatisfaction and disappointment at their failure to deliver what was ordered. A mention that it is precisely this crooked method of commerce that will drive you into the loving arms of the comptetition should warrant an explanation.

In the end, it's their f--k up so tell them and propose that they rectify their mistake.

It's possible that they will tell you to open the parcel and return the extra amount, for which you will be credited postage fees (if this can be done).

I must say that I've never had bad experiences with this sort of thing. Sure I've been sent the wrong thing etc, but usually once you communicate this to the company they will fix it at their expense. It's not your fault after all. Bad/lazy companies might require a bit of reminding, but you'll get it sorted in the end.

ok, I sent it back and they accepted it, pfew.

Thanks everyone for your help . And if I have not said it earlier, thanks for creating a great forum.