If Serum is being difficult, try these pregenerated serials.
SZMI-UIEP-ICQP-FGLI-ONKP
SIHC-YDFX-DPKY-GZKD-VQDX
SEFE-JSVD-EJJG-MHCS-URMQ
SYJF-YITA-CXUN-MIGX-MOHX