I tried to create a workflow rule and email alert when status is changed to pending resolution from pending ops on a case object.  This is my formula but it is not working.  Can someone help.

AND
(
ISCHANGED( Status ), PRIORVALUE(Status)= "Pending Ops", ISPICKVAL(Status,"Pending Resolution")
)

I have a multi pick list field called, Plays_c.  When the option "Retained Customer's Business" is chosen from this field the
single Pick list Type of Business_C field is required.   None of the other multi pick list values are required to pick type of business but the rule I created below is making it so.  How do I correct this.  I just want "Retained Customer's Business" to drive the type of business pick list.  Here is my current validation rule I have.
And(
INCLUDES(Plays__c, "Retained Customer's Business"),
ISBLANK(text(Type_of_Business__c)))

Any help would be awesome.
 

I tried to create a workflow rule and email alert when status is changed to pending resolution from pending ops on a case object.  This is my formula but it is not working.  Can someone help.

AND
(
ISCHANGED( Status ), PRIORVALUE(Status)= "Pending Ops", ISPICKVAL(Status,"Pending Resolution")
)

I have a multi pick list field called, Plays_c.  When the option "Retained Customer's Business" is chosen from this field the
single Pick list Type of Business_C field is required.   None of the other multi pick list values are required to pick type of business but the rule I created below is making it so.  How do I correct this.  I just want "Retained Customer's Business" to drive the type of business pick list.  Here is my current validation rule I have.
And(
INCLUDES(Plays__c, "Retained Customer's Business"),
ISBLANK(text(Type_of_Business__c)))

Any help would be awesome.