Hello Developers

i am new to the Salesforce, and i am trying to lear Formula fields, i have been given a task where Start Date and End date should show when custom field(Month__c) is selected, Now if i try to put Year, it shows error, 
 

Quota Start Date

DATE(
YEAR(TODAY()),
CASE(TEXT(Month__c), 
"January", 1, 
"February", 2,
"March", 3,
"April", 4,
"May", 5,
"June",6,
"July", 7,
"August",8, 
"September", 9,
"October", 10,
"November", 11,
"December", 12,
0),
1
)
----------------------------- 
Quota End Date

DATE(
YEAR(TODAY()),
CASE(TEXT(Month__c), 
"January", 1, 
"February", 2,
"March", 3,
"April", 4,
"May", 5,
"June",6,
"July", 7,
"August",8, 
"September", 9,
"October", 10,
"November", 11,
"December", 12,
0),
1
)

Now i want to add Picklist Field Name called Quater Year (Quater_Year__c), it consist of Number of Years from 2020 to 2030

So my requirement is when i select Picklist Quater Year as 2022 and Picklist Month as Jan, the Quota Start Date and Quota End Date should show for that particular Year i.e Jan 1st 2022 and Jan 31st 2022

but i am getting an error


How do i resolve this issue??

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