Storage.deleteValue generates “Out Of Memory Error”

When in effect my app does:

using Toybox.Application.Storage;

function delete(num) {

    var id=num/512;

   Storage.deleteValue(id);

}

delete(6658);

CIQ_LOG.YML says:

Error: Out Of Memory Error

Details: 'Failed invoking <symbol>'

Time: 2021-01-27T10:21:44Z

Part-Number: 006-B2700-00

Firmware-Version: '7.40'

Language-Code: eng

ConnectIQ-Version: 3.2.4

Filename: KERFSTOK

Appname: Kerfstok

Stack:

  - pc: 0x10006d44

  - pc: 0x10006e90

 

Storage.setValue(2,data) doesn’t generate problems.

I used this app for nearly a year multiple times a day without this problem.

How is this possible?