Answer

“Paacham” usually means the 5th tithi of the Jain lunar calendar.

If you mean the last Paacham before today, then I would need your location and Jain calendar tradition to answer accurately, because tithi timing can vary by place and by calendar method.

Clarification

Please tell me:

• Your city/country
• Whether you mean Sud Paacham or Vad Paacham
• If you mean a specific Jain month, such as Kartak, Magshar, Posh, etc.

Then I can help identify it more clearly.