Nippi,
Generally most mechanical seals failed because of misalignment. recommend you to check alignment and runout. Also ensure seal is properly cooled and lubricated. Consult seal vendor for specific seal type.
Have you check vibration at the type of tripping of pump on low current? If vibration level is high there must some issue with NPSHA. Check temp at pump suction. If possible share vibration level, make of the pump, flow rate, head, piping layout at pump suction.
Regards,
MSKhadke