Anyone living in Switzerland is familiar with the pink payment slips that regularly appear in the mail along with the all-too-frequent bills.

But a customer of Switzerland’s SBB was more than a little surprised recently to be sent a pink slip to help her pay a bill for the total of 0 francs and 0 cents.

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The customer pays 245 Swiss francs (€215) to the SBB every month for her yearly GA young adults GA travelcard which allows unlimited travel on the national public transport network.

But in October she received a letter stating: “Perhaps you have overlooked the fact that you have not yet paid the SBB the sum of 0.00 francs.”

The SBB then thanked the woman in advance for settling by October 8th using the attached payment slip.

The customer in question found the situation amusing, according to Swiss news site 20 Minuten. “But I find it strange that that the SBB invoiced me for zero francs and wasted paper for no reason,” she said.

The SBB meanwhile said it was aware of a handful of similar cases. A spokesperson said the bill had been paid too late and the printing of a reminder notice had already been triggered when details of her payment were received by the system.

The SBB said it as now looking at optimising the system so that this didn’t happen in future.

“The bill can be thrown away of course,” the spokesperson said.

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