Position cursor on end of block

What causes this issue?

You have selected the function "Select block". As
the start of the block, the system has taken the line on which the
cursor is positioned.

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?

In order to select the block, you must to the following:
Position the cursor on the last line to be selected.
Choose "Select block" again.

Error message extract from SAP system. Copyright SAP SE.