How to set if condition for formulas in excel?

How can I make an if statement in excel that will returns 999 if the A2 cell has this information (Your order qualifies for FREE Shipping Choose this option at checkout. See detail) otherwise print the number(for example for this information "This seller has only 375 of these available. To see if more are available from another seller, go to the product detail page." I would like to print 375). I attached what I've done by now. I will appreciate any help.

=IF(A2="Your order qualifies for FREE Shipping Choose this option at checkout. See detail",999,TEXTJOIN("",TRUE,IFERROR(MID(A2,ROW(INDIRECT("1:"&LEN(A2))),1)*1,"")))