On & you need to use change number & for processing

What causes this issue?

The characteristic has already been maintained on &v1& with
<DS:GLOS.change_number>change number</> &v2&.
However, you have entered a different change number. You can only make
changes with one change number on any one date.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

If you want to change the characteristic on &v1&, use change number
&v2&.

Error message extract from SAP system. Copyright SAP SE.