String palindrome via alphebetical compression

Question

Given a string consists of multiple alphabets, if its not a palindrome, compress TWO consecutive alphabets by value.
a =>1 b=>2 ....

The compression may occur more than once, given different situations.
If no possible compression can be made, give an appropriate message.

For example:
baaa should return ba(b)
dcad should return d(d)d
abab should return (c)(c)
jead & js should return not available for dual alphabetical compression

Compression resulting in a single alphabet will not be considered.

Answer 1

Bonus: for some special cases, such as jead, will require triple compression where three alphabets are compressed:
jead should be j(j) in this way.
Make the code available for the following examples as well:
abei should return (i)i
acbzdaa should return (f)z(f).
Good Luck, and have fun coding.

Answer 2

there are many constraints missing,

baaa => ba ( aa) => ba(b)
started from right end

dcad => d(ca)d => d(d)d
started from middle

acbzdaa => (ac)bzd(aa) => (d) bzd(b) => (db)z(db) => (f)z(f)
started from both ends,

need more clarification

Answer 3

Any kind of suggestion is encouraged to enhance this question after moderate consideration.

Answer 4

sayan if ba get compressed to c the final string would be caa which isnt a palindrome

Answer 5

baaa

its not pal.
why ba didnt get compressed as c????