Both got checked for chlamydia came back clean a month later both positive no cheating is this possible? m and f, both checked 6 months prior clean

YES: Chlamydia tests is BAD TEST of FIDELITY. Of course neither of you have cheated. False positive tests for the usual NAAT tests are not uncommon. False negative tests are even worse. It depends on who does it, which test it is. Gen probe is most sensitive and specific. Most likely two false negs. This VERY COMMON infection should be treated however. Then go out to dinner.

Probable misdiagnose: It is quite unfortunate that diagnostic tests still have false positive and false negative results which may lead to misdiagnoses and to mistreatments (over treatments and undertreatments).You may want to ask your chlamydia lab what technique was used (quantitative PCR diagnostic assay, a rapid culture, or a NAAT, Nucleic acid assay..) and what's the accuracy of the test (sensitiv/ specif/pred.val