surya88 Hello, which domain are you trying to add exactly?
error message Invalid domain or unrecognized TLD is pretty self explanatory, the TLD list is either missing or the domain is invalid, check if the tld exists in public_suffix_list.dat file, example:
grep .com /etc/openpanel/openpanel/conf/public_suffix_list.dat
if it does exists, please share the domain to try and reproduce this
you can re-download the file if needed:
wget --timeout=5 --tries=3 -q --inet4-only -O /etc/openpanel/openpanel/conf/public_suffix_list.dat https://publicsuffix.org/list/public_suffix_list.dat