4-2-3-1 Advice

Hi i need some help with my tactic it has served very well up until now.... I have gone 10 games with only taking 3 points. Can anyone tell me what is wrong? Defense was always solid for the 4 years i used this tactic and now all of a sudden its a shambles at the back... conceding 3+ goals a game and getting smashed by crappy teams.
My team is quality year 2021 (lots of regens)

Attacking
Balanced

GK(D)

RB(D) CB(D) CB(D) LB(D)

CM(S) BWM(D)

W(A) AP(S) W(A)

CF(A)


Shorter Passing
Pass Into Space
Run at Defence
Exploit the Flanks
Push up Higher
Hassle Oponents
Tighter Marking
Higher Tempo
More Expressive
Play Wider

No SS because I am at work...Bored! lol

Please help!!