MySQL Character set error illegal mix of collations

SELECT * from Mobile_card.mcc_o2o_repayment_request Orr INNER JOIN BI_O2O_SFQ. CARD C on c.cardid = Orr.cardno LIMIT 0,

Error code:1267. Illegal mix of collations (utf8_general_ci,implicit) and (utf8_unicode_ci,implicit) for operation ' = ' 0.038 sec

This is a MySQL character set error

SELECT *

From

Mobile_card.mcc_o2o_repayment_request Orr

INNER JOIN

Bi_o2o_sfq. CARD C on c.cardid = Orr.cardno COLLATE utf8_unicode_ci

To the wrong character set, give a forced conversion to add COLLATE utf8_unicode_ci

MySQL Character set error illegal mix of collations