Provider needs some fixing(?)

QUOTE:
[0] NVDA Error: The remote server returned an error: (422) Unprocessable Entity.
[1] REGN 7329 bars 5/4/2020 0 bars added
[8] QCOM 7149 bars 5/4/2020 0 bars added
[5] PYPL Error: The remote server returned an error: (422) Unprocessable Entity.
[7] SBUX 7015 bars 5/4/2020 0 bars added
[9] PCAR Error: The remote server returned an error: (422) Unprocessable Entity.
[6] PAYX 7586 bars 5/4/2020 0 bars added
[4] ROST 8525 bars 5/4/2020 0 bars added
[3] PEP 12086 bars 5/4/2020 0 bars added
[2] SGEN Error: The remote server returned an error: (422) Unprocessable Entity.

There's nothing to fix, everything works as expected:

Updating DataSet TEST ...
Preparing requests ...
Requests are ready to go.
Yahoo session cookie cached
Updating Security Names for 4 symbols...
Security Names updated.
[1] PYPL 1217 bars 04.05.2020 1217 bars added
[0] NVDA 5355 bars 04.05.2020 5355 bars added
[3] SGEN 4818 bars 04.05.2020 4818 bars added
[2] PCAR 10120 bars 04.05.2020 10120 bars added
Update completed (4.106 sec)
----------------

Please retry at a different time or from a different IP address. It happens to free data feeds (and even to subscription-based ones).

Your are right . The issue looks to effect randomly. Thanks for your input.
First run

QUOTE:
[7] NVDA 5355 bars 5/4/2020 4 bars added 4 bars corrected
[4] NTRS 7586 bars 5/4/2020 0 bars added 1 bars corrected
[6] MRO 12698 bars 5/4/2020 0 bars added 2 bars corrected
[8] PFG 4664 bars 5/4/2020 0 bars added 2 bars corrected
[2] PH 8782 bars 5/4/2020 0 bars added 2 bars corrected
[3] PNR 11856 bars 5/4/2020 0 bars added 2 bars corrected
[0] PRU 4628 bars 5/4/2020 0 bars added 1 bars corrected
[1] PXD 5721 bars 5/4/2020 0 bars added 1 bars corrected
[7] QRVO 1343 bars 5/4/2020 0 bars added 1 bars corrected
[5] QCOM 7149 bars 5/4/2020 0 bars added 2 bars correcte

2nd run (updating a different data set)

QUOTE:
[4] USPH Error: The remote server returned an error: (422) Unprocessable Entity.
[3] UTHR 5254 bars 5/4/2020 0 bars added 2 bars corrected
[7] UUU 6220 bars 5/4/2020 0 bars added 1 bars corrected
[0] UTX Error: The remote server returned an error: (422) Unprocessable Entity.
[6] UTL 7086 bars 5/4/2020 0 bars added 1 bars corrected
[4] VAC 2134 bars 5/4/2020 0 bars added 1 bars corrected
[5] V 3053 bars 5/4/2020 0 bars added 2 bars corrected
[2] UVXY 2160 bars 5/4/2020 0 bars added 2 bars corrected
[8] UVE Error: The remote server returned an error: (422) Unprocessable Entity.
[1] UWN Error: The remote server returned an error: (404) Not Found.
[3] VAL 6639 bars 5/4/2020 0 bars added 2 bars corrected
[9] UVV 8148 bars 5/4/2020 0 bars added 2 bars corrected
[6] VC 2411 bars 5/4/2020 0 bars added 1 bars corrected
[0] VAR 8148 bars 5/4/2020 0 bars added 1 bars corrected
[8] VEC 1418 bars 5/4/2020 0 bars added 1 bars corrected
[2] VEA 3218 bars 5/4/2020 0 bars added 1 bars corrected
[4] VCRA Error: The remote server returned an error: (422) Unprocessable Entity.

Good to know it.

From my experience, on a couple occasions Yahoo threw this Error 422 where in fact it should be Error 404 i.e. symbol not found (invalid ticker).

Error 422 is a temporary condition. If you experience it, retry after a while.