Problems erasing marketing attributes after adding them by a code snippet

Hi experts,

The problem I'm facing occurs after adding some marketing attributes with the corresponding values to a BP using the FM 'CRM_MKTBP_CHANGE_BP'. I also tried the FM 'CRM_MKTBP_ASSIGN_ATTRIBUT'.

All this work is done properly but the problem starts when I access to the details of the BP, via WebUI, and try to erase the created marketing attributes. When i erase them all and press the save button, they appear again. Anything happens. The only way I have to erase them is using another FM, but it is impossible to do that via WebUI.

Any suggestion?

Thank you very much.