Sounds like you did EVERYTHING correct! I assume that you used a OE NAME brand (MB or Nippondenso) rebuilt A/C compressor! IF not then failure on many aftermarket compressors after 1 year is VERY common.

When converting from R12 to R134a use only 70% of the original fill.
ALWAYS use PAG iso46 Oil when converting MB Denso compressors.

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