diff --git a/addons/account/models/sequence_mixin.py b/addons/account/models/sequence_mixin.py
index bf84c468579..231448b3668 100644
--- a/addons/account/models/sequence_mixin.py
+++ b/addons/account/models/sequence_mixin.py
@@ -21,8 +21,8 @@ class SequenceMixin(models.AbstractModel):
     _sequence_field = "name"
     _sequence_date_field = "date"
     _sequence_index = False
-    _sequence_monthly_regex = r'^(?P<prefix1>.*?)(?P<year>((?<=\D)|(?<=^))((20|21)\d{2}|(\d{2}(?=\D))))(?P<prefix2>\D*?)(?P<month>(0[1-9]|1[0-2]))(?P<prefix3>\D+?)(?P<seq>\d*)(?P<suffix>\D*?)$'
-    _sequence_yearly_regex = r'^(?P<prefix1>.*?)(?P<year>((?<=\D)|(?<=^))((20|21)?\d{2}))(?P<prefix2>\D+?)(?P<seq>\d*)(?P<suffix>\D*?)$'
+    _sequence_monthly_regex = r'^(?P<prefix1>.*?)(?P<year>((?<=\D)|(?<=^))((19|20|21)\d{2}|(\d{2}(?=\D))))(?P<prefix2>\D*?)(?P<month>(0[1-9]|1[0-2]))(?P<prefix3>\D+?)(?P<seq>\d*)(?P<suffix>\D*?)$'
+    _sequence_yearly_regex = r'^(?P<prefix1>.*?)(?P<year>((?<=\D)|(?<=^))((19|20|21)?\d{2}))(?P<prefix2>\D+?)(?P<seq>\d*)(?P<suffix>\D*?)$'
     _sequence_fixed_regex = r'^(?P<prefix1>.*?)(?P<seq>\d{0,9})(?P<suffix>\D*?)$'
 
     sequence_prefix = fields.Char(compute='_compute_split_sequence', store=True)