Few lines Relative abundance output of QIIME2:

k__Bacteria;p__Firmicutes;c__Clostridia;o__Clostridiales;f__Lachnospiraceae;**g__Blautia;s__Dorea formicigenerans**
k__Bacteria;p__Firmicutes;c__Clostridia;o__Clostridiales;f__Lachnospiraceae;**g__Blautia**;**s__Eubacterium oxidoreducens**
k__Bacteria;p__Firmicutes;c__Clostridia;o__Clostridiales;f__Lachnospiraceae;**g__Lacrimispora;s__Merdimonas faecis**
k__Bacteria;p__Firmicutes;c__Clostridia;o__Clostridiales;f__Ruminococcaceae;**g__Pseudoflavonifractor;s__Flavonifractor plautii**

I am getting this type of classification where, in genus it mention one, and in species it is totally different from the genus mentioned. I don't know how to interpret this or the reason why it occurs. Could anyone help me in this one?