Cant figure out IF statement syntax error

Hello,

I have a nested IF statement shown below that seems to have correct logic yet I am getting an odd error.

Formula used in the UI-Only field:

IF({{NRR}} <= 100, ({{OriginalBook}}-{{BookWon}})*0.0025, IF({{NRR}} > 100 &amp;&amp; <= 120, {{OriginalBook}}*0.0025 + ({{BookWon}}-{{OriginalBook}})*0.0075, {{OriginalBook}}*0.0025 + ({{OriginalBook}}*0.25)*0.0075 + ({{BookWon}}-({{OriginalBook}}*1.25))*0.015))

Error:

SyntaxError: Expected "'", "(", ".", """", "date", "false", "null", "true", "undefined", [ x0C

	x0B    -      ], [0-9], [-+!], or [a-z] but "<" found. 

{{NRR}} is another formula field returning a number.