How to clear cell value if it's N/A?

Using monday as CRM hub that collects data from different sources.
Some data sources cannot integrate directly with Monday and I pass data to Slack and then using Zapier to Monday which works just fine. The problem I am facing is that when info is not available for certain points it passes ‘Not specified’, ‘N/A’, or ‘–’.

I use chart data for reporting and it reports on those values, which I want to avoid.

Is there a way to set it up If ‘cell-value’ is ‘Not Specified’ - clear (remove text/leave cell empty)?