I know this has been posted a few times but none of the solutions seemed to woprk. I am an amateur and would appreciate any help I can get.
There are numerous websites which show us an Access Denied error and our ISP keeps directing us to an issue with our Mikrotik router. When I tracert a website that doesn't work. it'll time out and show:
Tracing route to gap.com [23.59.17.159]
over a maximum of 30 hops:

1 <1 ms 1 ms <1 ms 192.168.1.1
2 2 ms 1 ms 1 ms lo0-100.NYCMNY-VFTTP-326.verizon-gni.net [96.239.35.1]
3 13 ms 2 ms 2 ms B3326.NYCMNY-LCR-21.verizon-gni.net [100.41.131.157]
4 * * * Request timed out.
5 * * * Request timed out.
6 * * * Request timed out.
7 19 ms 19 ms 20 ms 0.ae9.GW7.CHI13.ALTER.NET [140.222.234.221]
8 27 ms 179 ms 245 ms verizon.com.customer.alter.net [152.179.92.222]
9 19 ms 18 ms 18 ms a23-59-17-159.deploy.static.akamaitechnologies.com [23.59.17.159]

Trace complete.

I've tried the fix below but it still doesn't let me acces these webpages. What can I try?

/ip firewall mangle

add action=change-mss chain=forward in-interface=ether1 new-mss=clamp-to-pmtu \

passthrough=no protocol=tcp tcp-flags=syn tcp-mss=1453-65535

add action=change-mss chain=forward new-mss=clamp-to-pmtu out-interface=ether1 \

passthrough=no protocol=tcp tcp-flags=syn tcp-mss=1453-65535