A column with a text format in Excel to remain when imported into looker studio

Hi all, 

I have an excel file which contains a column (formatted as Text). The values are as follows 2.2, 2.3, 2.20, 2.22.

However, once I import them into looker studio, the column is automatically read as number and the value of 2.20 becomes 2.2. Although I went to 'Resource' --> 'Manage added data source' to change the type there from number to text. 

I followed some advice from the internet saying that I need to ensure the format in excel is text, or i can simply format the number in looker studio by having 2 decimal numbers (although this will only transform the original 2.2 into 2.20 instead. So what i want is that the numbers will be the same as shown in excel.. 2.2 remains 2.2 and 2.20 remains 2.20 as text. 

Can anyone help please? 

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