Update BBHX_Phenom.py

BBHX_Phenom.py

@@ -177,7 +177,7 @@ def _bbhx_fd(
         If true, the BBHx waveform generator is cached based on the computed
         ``mf_min``. Must be ``False`` if ``mf_min`` is specfied.
     enable_flower_warn: bool
-        If False, it will turn off the warnning from `f_lower` calculation.
+        If False, it will turn off the warning from `f_lower` calculation.
     
     Returns
     -------
@@ -243,9 +243,8 @@ def _bbhx_fd(
             t0=0
         )
     else:
-        err_msg = f"Don't recognise reference frame {ref_frame}. "
-        err_msg = f"Known frames are 'LISA' and 'SSB'."
-        ValueError(err_msg, RuntimeWarning)
+        err_msg = f"Don't recognise reference frame {ref_frame}. Known frames are 'LISA' and 'SSB'."
+        raise ValueError(err_msg)
 
     # We follow the convention used in LAL and set the frequency based on the
     # highest m mode. This means that lower m modes will start at later times.
@@ -283,8 +282,8 @@ def _bbhx_fd(
                 f_lower=interp_f_lower,
             )
             f_min_tobs = tf_track(t_obs_start) # in Hz
-        if np.abs(f_min - f_min_tobs) / f_min > 1e-2 and enable_flower_warn:
-            err_msg = f"Input 'f_lower' is significantly deviated from the value calculated from 't_obs_start'."
+        if enable_flower_warn and f_min < f_min_tobs:
+            err_msg = f"Input 'f_lower' is lower than the value calculated from 't_obs_start'."
             warn(err_msg, RuntimeWarning)
 
     # We want to cache the waveform generator, but as it takes a mass dependent
@@ -408,4 +407,4 @@ def _bbhx_fd(
     if str(tdi) not in ['1.5', '2.0']:
         raise ValueError("The TDI version only supports '1.5' and '2.0' for now.")
 
-    return output
+    return output